2024-01-24 05:14:11

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 00/14] Split crash out from kexec and clean up related config items

Motivation:
=============
Previously, LKP reported a building error. When investigating, it can't
be resolved reasonablly with the present messy kdump config items.

https://lore.kernel.org/oe-kbuild-all/[email protected]/

The kdump (crash dumping) related config items could causes confusions:

Firstly,
---
CRASH_CORE enables codes including
- crashkernel reservation;
- elfcorehdr updating;
- vmcoreinfo exporting;
- crash hotplug handling;

Now fadump of powerpc, kcore dynamic debugging and kdump all selects
CRASH_CORE, while fadump
- fadump needs crashkernel parsing, vmcoreinfo exporting, and accessing
global variable 'elfcorehdr_addr';
- kcore only needs vmcoreinfo exporting;
- kdump needs all of the current kernel/crash_core.c.

So only enabling PROC_CORE or FA_DUMP will enable CRASH_CORE, this
mislead people that we enable crash dumping, actual it's not.

Secondly,
---
It's not reasonable to allow KEXEC_CORE select CRASH_CORE.

Because KEXEC_CORE enables codes which allocate control pages, copy
kexec/kdump segments, and prepare for switching. These codes are
shared by both kexec reboot and kdump. We could want kexec reboot,
but disable kdump. In that case, CRASH_CORE should not be selected.

--------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC=y
CONFIG_KEXEC_FILE=y
---------------------

Thirdly,
---
It's not reasonable to allow CRASH_DUMP select KEXEC_CORE.

That could make KEXEC_CORE, CRASH_DUMP are enabled independently from
KEXEC or KEXEC_FILE. However, w/o KEXEC or KEXEC_FILE, the KEXEC_CORE
code built in doesn't make any sense because no kernel loading or
switching will happen to utilize the KEXEC_CORE code.
---------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
---------------------

In this case, what is worse, on arch sh and arm, KEXEC relies on MMU,
while CRASH_DUMP can still be enabled when !MMU, then compiling error is
seen as the lkp test robot reported in above link.

------arch/sh/Kconfig------
config ARCH_SUPPORTS_KEXEC
def_bool MMU

config ARCH_SUPPORTS_CRASH_DUMP
def_bool BROKEN_ON_SMP
---------------------------

Changes:
===========
1, split out crash_reserve.c from crash_core.c;
2, split out vmcore_infoc. from crash_core.c;
3, move crash related codes in kexec_core.c into crash_core.c;
4, remove dependency of FA_DUMP on CRASH_DUMP;
5, clean up kdump related config items;
6, wrap up crash codes in crash related ifdefs on all 8 arch-es
which support crash dumping, except of ppc;

Achievement:
===========
With above changes, I can rearrange the config item logic as below (the right
item depends on or is selected by the left item):

PROC_KCORE -----------> VMCORE_INFO

|----------> VMCORE_INFO
FA_DUMP----|
|----------> CRASH_RESERVE

---->VMCORE_INFO
/
|---->CRASH_RESERVE
KEXEC --| /|
|--> KEXEC_CORE--> CRASH_DUMP-->/-|---->PROC_VMCORE
KEXEC_FILE --| \ |
\---->CRASH_HOTPLUG


KEXEC --|
|--> KEXEC_CORE (for kexec reboot only)
KEXEC_FILE --|

Test
========
On all 8 architectures, including x86_64, arm64, s390x, sh, arm, mips,
riscv, loongarch, I did below three cases of config item setting and
building all passed. Take configs on x86_64 as exampmle here:

(1) Both CONFIG_KEXEC and KEXEC_FILE is unset, then all kexec/kdump
items are unset automatically:
# Kexec and crash features
# CONFIG_KEXEC is not set
# CONFIG_KEXEC_FILE is not set
# end of Kexec and crash features

(2) set CONFIG_KEXEC_FILE and 'make olddefconfig':
---------------
# Kexec and crash features
CONFIG_CRASH_RESERVE=y
CONFIG_VMCORE_INFO=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
CONFIG_CRASH_DUMP=y
CONFIG_CRASH_HOTPLUG=y
CONFIG_CRASH_MAX_MEMORY_RANGES=8192
# end of Kexec and crash features
---------------

(3) unset CONFIG_CRASH_DUMP in case 2 and execute 'make olddefconfig':
------------------------
# Kexec and crash features
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC_FILE=y
# end of Kexec and crash features
------------------------

Note:
For ppc, it needs investigation to make clear how to split out crash
code in arch folder. Hope Hari and Pingfan can help have a look, see if
it's doable. Now, I make it either have both kexec and crash enabled, or
disable both of them altogether.

Changelog
==========
v2->v3:
- In patch 2, there's conflict when rebasing to linux-next in
kernel/crash_core.c because of below commits from Uladzislau:
- commit 699d9351822e ("mm: vmalloc: Fix a warning in the crash_save_vmcoreinfo_init()")
- commit 5f4c0c1e2a51 (:mm/vmalloc: remove vmap_area_list")
- In patch 13, fix the lkp reported issue by using CONFIG_CRASH_RESERVE
ifdef, giving up the earlier IS_ENABLED(CONFIG_CRASH_RESERVE) checking in v2.
- In patch 14, update code change after below commit merged into
mainline:
- commit 78de91b45860 ("LoongArch: Use generic interface to support crashkernel=X,[high,low]")

Baoquan He (14):
kexec: split crashkernel reservation code out from crash_core.c
crash: split vmcoreinfo exporting code out from crash_core.c
crash: remove dependency of FA_DUMP on CRASH_DUMP
crash: split crash dumping code out from kexec_core.c
crash: clean up kdump related config items
x86, crash: wrap crash dumping code into crash related ifdefs
arm64, crash: wrap crash dumping code into crash related ifdefs
ppc, crash: enforce KEXEC and KEXEC_FILE to select CRASH_DUMP
s390, crash: wrap crash dumping code into crash related ifdefs
sh, crash: wrap crash dumping code into crash related ifdefs
mips, crash: wrap crash dumping code into crash related ifdefs
riscv, crash: wrap crash dumping code into crash related ifdefs
arm, crash: wrap crash dumping code into crash related ifdefs
loongarch, crash: wrap crash dumping code into crash related ifdefs

arch/arm/kernel/setup.c | 4 +-
arch/arm64/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 4 +-
arch/arm64/include/asm/kexec.h | 2 +-
arch/arm64/kernel/Makefile | 2 +-
arch/arm64/kernel/machine_kexec.c | 2 +-
arch/arm64/kernel/machine_kexec_file.c | 10 +-
.../kernel/{crash_core.c => vmcore_info.c} | 2 +-
arch/arm64/mm/init.c | 2 +-
arch/loongarch/kernel/setup.c | 2 +-
arch/mips/kernel/setup.c | 17 +-
arch/powerpc/Kconfig | 9 +-
arch/powerpc/kernel/setup-common.c | 2 +-
arch/powerpc/mm/nohash/kaslr_booke.c | 4 +-
arch/powerpc/platforms/powernv/opal-core.c | 2 +-
arch/riscv/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 4 +-
arch/riscv/kernel/Makefile | 2 +-
arch/riscv/kernel/elf_kexec.c | 9 +-
.../kernel/{crash_core.c => vmcore_info.c} | 2 +-
arch/riscv/mm/init.c | 2 +-
arch/s390/kernel/kexec_elf.c | 2 +
arch/s390/kernel/kexec_image.c | 2 +
arch/s390/kernel/machine_kexec_file.c | 10 +
arch/sh/kernel/machine_kexec.c | 3 +
arch/sh/kernel/setup.c | 2 +-
arch/x86/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 6 +-
arch/x86/kernel/Makefile | 6 +-
arch/x86/kernel/cpu/mshyperv.c | 4 +
arch/x86/kernel/kexec-bzimage64.c | 4 +
arch/x86/kernel/kvm.c | 4 +-
arch/x86/kernel/machine_kexec_64.c | 3 +
arch/x86/kernel/reboot.c | 2 +-
arch/x86/kernel/setup.c | 2 +-
arch/x86/kernel/smp.c | 2 +-
.../{crash_core_32.c => vmcore_info_32.c} | 2 +-
.../{crash_core_64.c => vmcore_info_64.c} | 2 +-
arch/x86/xen/enlighten_hvm.c | 4 +
drivers/base/cpu.c | 6 +-
drivers/firmware/qemu_fw_cfg.c | 14 +-
fs/proc/Kconfig | 2 +-
fs/proc/kcore.c | 2 +-
include/linux/buildid.h | 2 +-
include/linux/crash_core.h | 152 ++--
include/linux/crash_reserve.h | 48 ++
include/linux/kexec.h | 47 +-
include/linux/vmcore_info.h | 81 ++
init/initramfs.c | 2 +-
kernel/Kconfig.kexec | 12 +-
kernel/Makefile | 5 +-
kernel/crash_core.c | 762 +++++-------------
kernel/crash_reserve.c | 464 +++++++++++
kernel/{crash_dump.c => elfcorehdr.c} | 0
kernel/kexec.c | 11 +-
kernel/kexec_core.c | 250 +-----
kernel/kexec_file.c | 13 +-
kernel/kexec_internal.h | 2 +
kernel/ksysfs.c | 10 +-
kernel/printk/printk.c | 4 +-
kernel/vmcore_info.c | 231 ++++++
lib/buildid.c | 2 +-
62 files changed, 1228 insertions(+), 1043 deletions(-)
rename arch/arm64/include/asm/{crash_core.h => crash_reserve.h} (81%)
rename arch/arm64/kernel/{crash_core.c => vmcore_info.c} (97%)
rename arch/riscv/include/asm/{crash_core.h => crash_reserve.h} (78%)
rename arch/riscv/kernel/{crash_core.c => vmcore_info.c} (96%)
rename arch/x86/include/asm/{crash_core.h => crash_reserve.h} (92%)
rename arch/x86/kernel/{crash_core_32.c => vmcore_info_32.c} (90%)
rename arch/x86/kernel/{crash_core_64.c => vmcore_info_64.c} (94%)
create mode 100644 include/linux/crash_reserve.h
create mode 100644 include/linux/vmcore_info.h
create mode 100644 kernel/crash_reserve.c
rename kernel/{crash_dump.c => elfcorehdr.c} (100%)
create mode 100644 kernel/vmcore_info.c

--
2.41.0



2024-01-24 05:14:20

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 01/14] kexec: split crashkernel reservation code out from crash_core.c

Both kdump and fa_dump of ppc rely on crashkernel reservation. Move the
relevant codes into separate files:
crash_reserve.c, include/linux/crash_reserve.h.

And also add config item CRASH_RESERVE to control its enabling of the
codes. And update config items which has relationship with crashkernel
reservation.

And also change ifdeffery from CONFIG_CRASH_CORE to CONFIG_CRASH_RESERVE
when those scopes are only crashkernel reservation related.

And also rename arch/XXX/include/asm/{crash_core.h => crash_reserve.h}
on arm64, x86 and risc-v because those architectures' crash_core.h
is only related to crashkernel reservation.

Signed-off-by: Baoquan He <[email protected]>
---
arch/arm64/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 4 +-
arch/powerpc/Kconfig | 1 +
arch/powerpc/mm/nohash/kaslr_booke.c | 4 +-
arch/riscv/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 4 +-
arch/x86/Kconfig | 2 +-
.../asm/{crash_core.h => crash_reserve.h} | 6 +-
include/linux/crash_core.h | 40 --
include/linux/crash_reserve.h | 48 ++
include/linux/kexec.h | 1 +
kernel/Kconfig.kexec | 5 +-
kernel/Makefile | 1 +
kernel/crash_core.c | 438 -----------------
kernel/crash_reserve.c | 464 ++++++++++++++++++
15 files changed, 531 insertions(+), 491 deletions(-)
rename arch/arm64/include/asm/{crash_core.h => crash_reserve.h} (81%)
rename arch/riscv/include/asm/{crash_core.h => crash_reserve.h} (78%)
rename arch/x86/include/asm/{crash_core.h => crash_reserve.h} (92%)
create mode 100644 include/linux/crash_reserve.h
create mode 100644 kernel/crash_reserve.c

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 3d2300aca238..96fb363d2f52 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1520,7 +1520,7 @@ config ARCH_SUPPORTS_CRASH_DUMP
def_bool y

config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
- def_bool CRASH_CORE
+ def_bool CRASH_RESERVE

config TRANS_TABLE
def_bool y
diff --git a/arch/arm64/include/asm/crash_core.h b/arch/arm64/include/asm/crash_reserve.h
similarity index 81%
rename from arch/arm64/include/asm/crash_core.h
rename to arch/arm64/include/asm/crash_reserve.h
index 9f5c8d339f44..4afe027a4e7b 100644
--- a/arch/arm64/include/asm/crash_core.h
+++ b/arch/arm64/include/asm/crash_reserve.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0-only */
-#ifndef _ARM64_CRASH_CORE_H
-#define _ARM64_CRASH_CORE_H
+#ifndef _ARM64_CRASH_RESERVE_H
+#define _ARM64_CRASH_RESERVE_H

/* Current arm64 boot protocol requires 2MB alignment */
#define CRASH_ALIGN SZ_2M
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index b9fc064d38d2..7f704ae5c5ef 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -691,6 +691,7 @@ config FA_DUMP
bool "Firmware-assisted dump"
depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
select CRASH_CORE
+ select CRASH_RESERVE
select CRASH_DUMP
help
A robust mechanism to get reliable kernel crash dump with
diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index b4f2786a7d2b..cdff129abb14 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c
@@ -13,7 +13,7 @@
#include <linux/delay.h>
#include <linux/memblock.h>
#include <linux/libfdt.h>
-#include <linux/crash_core.h>
+#include <linux/crash_reserve.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <asm/cacheflush.h>
@@ -173,7 +173,7 @@ static __init bool overlaps_region(const void *fdt, u32 start,

static void __init get_crash_kernel(void *fdt, unsigned long size)
{
-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_CRASH_RESERVE
unsigned long long crash_size, crash_base;
int ret;

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 69d24f513922..7c6869e43a4a 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -767,7 +767,7 @@ config ARCH_SUPPORTS_CRASH_DUMP
def_bool y

config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
- def_bool CRASH_CORE
+ def_bool CRASH_RESERVE

config COMPAT
bool "Kernel support for 32-bit U-mode"
diff --git a/arch/riscv/include/asm/crash_core.h b/arch/riscv/include/asm/crash_reserve.h
similarity index 78%
rename from arch/riscv/include/asm/crash_core.h
rename to arch/riscv/include/asm/crash_reserve.h
index e1874b23feaf..013962e63587 100644
--- a/arch/riscv/include/asm/crash_core.h
+++ b/arch/riscv/include/asm/crash_reserve.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0-only */
-#ifndef _RISCV_CRASH_CORE_H
-#define _RISCV_CRASH_CORE_H
+#ifndef _RISCV_CRASH_RESERVE_H
+#define _RISCV_CRASH_RESERVE_H

#define CRASH_ALIGN PMD_SIZE

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 502986237cb6..a9243e0948a3 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2106,7 +2106,7 @@ config ARCH_SUPPORTS_CRASH_HOTPLUG
def_bool y

config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
- def_bool CRASH_CORE
+ def_bool CRASH_RESEERVE

config PHYSICAL_START
hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
diff --git a/arch/x86/include/asm/crash_core.h b/arch/x86/include/asm/crash_reserve.h
similarity index 92%
rename from arch/x86/include/asm/crash_core.h
rename to arch/x86/include/asm/crash_reserve.h
index 76af98f4e801..152239f95541 100644
--- a/arch/x86/include/asm/crash_core.h
+++ b/arch/x86/include/asm/crash_reserve.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _X86_CRASH_CORE_H
-#define _X86_CRASH_CORE_H
+#ifndef _X86_CRASH_RESERVE_H
+#define _X86_CRASH_RESERVE_H

/* 16M alignment for crash kernel regions */
#define CRASH_ALIGN SZ_16M
@@ -39,4 +39,4 @@ static inline unsigned long crash_low_size_default(void)
#endif
}

-#endif /* _X86_CRASH_CORE_H */
+#endif /* _X86_CRASH_RESERVE_H */
diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
index 9eaeaafe0cad..1fde49246fa6 100644
--- a/include/linux/crash_core.h
+++ b/include/linux/crash_core.h
@@ -5,14 +5,6 @@
#include <linux/linkage.h>
#include <linux/elfcore.h>
#include <linux/elf.h>
-#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
-#include <asm/crash_core.h>
-#endif
-
-/* Location of a reserved region to hold the crash kernel.
- */
-extern struct resource crashk_res;
-extern struct resource crashk_low_res;

#define CRASH_CORE_NOTE_NAME "CORE"
#define CRASH_CORE_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
@@ -87,38 +79,6 @@ Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
void *data, size_t data_len);
void final_note(Elf_Word *buf);

-int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
- unsigned long long *crash_size, unsigned long long *crash_base,
- unsigned long long *low_size, bool *high);
-
-#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
-#ifndef DEFAULT_CRASH_KERNEL_LOW_SIZE
-#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
-#endif
-#ifndef CRASH_ALIGN
-#define CRASH_ALIGN SZ_2M
-#endif
-#ifndef CRASH_ADDR_LOW_MAX
-#define CRASH_ADDR_LOW_MAX SZ_4G
-#endif
-#ifndef CRASH_ADDR_HIGH_MAX
-#define CRASH_ADDR_HIGH_MAX memblock_end_of_DRAM()
-#endif
-
-void __init reserve_crashkernel_generic(char *cmdline,
- unsigned long long crash_size,
- unsigned long long crash_base,
- unsigned long long crash_low_size,
- bool high);
-#else
-static inline void __init reserve_crashkernel_generic(char *cmdline,
- unsigned long long crash_size,
- unsigned long long crash_base,
- unsigned long long crash_low_size,
- bool high)
-{}
-#endif
-
/* Alignment required for elf header segment */
#define ELF_CORE_HEADER_ALIGN 4096

diff --git a/include/linux/crash_reserve.h b/include/linux/crash_reserve.h
new file mode 100644
index 000000000000..5a9df944fb80
--- /dev/null
+++ b/include/linux/crash_reserve.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_CRASH_RESERVE_H
+#define LINUX_CRASH_RESERVE_H
+
+#include <linux/linkage.h>
+#include <linux/elfcore.h>
+#include <linux/elf.h>
+#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
+#include <asm/crash_reserve.h>
+#endif
+
+/* Location of a reserved region to hold the crash kernel.
+ */
+extern struct resource crashk_res;
+extern struct resource crashk_low_res;
+
+int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
+ unsigned long long *crash_size, unsigned long long *crash_base,
+ unsigned long long *low_size, bool *high);
+
+#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
+#ifndef DEFAULT_CRASH_KERNEL_LOW_SIZE
+#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
+#endif
+#ifndef CRASH_ALIGN
+#define CRASH_ALIGN SZ_2M
+#endif
+#ifndef CRASH_ADDR_LOW_MAX
+#define CRASH_ADDR_LOW_MAX SZ_4G
+#endif
+#ifndef CRASH_ADDR_HIGH_MAX
+#define CRASH_ADDR_HIGH_MAX memblock_end_of_DRAM()
+#endif
+
+void __init reserve_crashkernel_generic(char *cmdline,
+ unsigned long long crash_size,
+ unsigned long long crash_base,
+ unsigned long long crash_low_size,
+ bool high);
+#else
+static inline void __init reserve_crashkernel_generic(char *cmdline,
+ unsigned long long crash_size,
+ unsigned long long crash_base,
+ unsigned long long crash_low_size,
+ bool high)
+{}
+#endif
+#endif /* LINUX_CRASH_RESERVE_H */
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 400cb6c02176..6d79bfb52e5b 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -16,6 +16,7 @@
#if !defined(__ASSEMBLY__)

#include <linux/crash_core.h>
+#include <linux/crash_reserve.h>
#include <asm/io.h>
#include <linux/range.h>

diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec
index 946dffa048b7..8b7be71edd85 100644
--- a/kernel/Kconfig.kexec
+++ b/kernel/Kconfig.kexec
@@ -2,11 +2,15 @@

menu "Kexec and crash features"

+config CRASH_RESERVE
+ bool
+
config CRASH_CORE
bool

config KEXEC_CORE
select CRASH_CORE
+ select CRASH_RESERVE
bool

config KEXEC_ELF
@@ -96,7 +100,6 @@ config KEXEC_JUMP
config CRASH_DUMP
bool "kernel crash dumps"
depends on ARCH_SUPPORTS_CRASH_DUMP
- select CRASH_CORE
select KEXEC_CORE
help
Generate crash dump after being started by kexec.
diff --git a/kernel/Makefile b/kernel/Makefile
index ce105a5558fc..05fa88b3ab74 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_KALLSYMS_SELFTEST) += kallsyms_selftest.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_CRASH_CORE) += crash_core.o
+obj-$(CONFIG_CRASH_RESERVE) += crash_reserve.o
obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 49b31e59d3cc..ae0d1ce89b46 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -34,444 +34,6 @@ u32 *vmcoreinfo_note;
/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
static unsigned char *vmcoreinfo_data_safecopy;

-/* Location of the reserved area for the crash kernel */
-struct resource crashk_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
- .desc = IORES_DESC_CRASH_KERNEL
-};
-struct resource crashk_low_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
- .desc = IORES_DESC_CRASH_KERNEL
-};
-
-/*
- * parsing the "crashkernel" commandline
- *
- * this code is intended to be called from architecture specific code
- */
-
-
-/*
- * This function parses command lines in the format
- *
- * crashkernel=ramsize-range:size[,...][@offset]
- *
- * The function returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_mem(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- char *cur = cmdline, *tmp;
- unsigned long long total_mem = system_ram;
-
- /*
- * Firmware sometimes reserves some memory regions for its own use,
- * so the system memory size is less than the actual physical memory
- * size. Work around this by rounding up the total size to 128M,
- * which is enough for most test cases.
- */
- total_mem = roundup(total_mem, SZ_128M);
-
- /* for each entry of the comma-separated list */
- do {
- unsigned long long start, end = ULLONG_MAX, size;
-
- /* get the start of the range */
- start = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("crashkernel: Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (*cur != '-') {
- pr_warn("crashkernel: '-' expected\n");
- return -EINVAL;
- }
- cur++;
-
- /* if no ':' is here, than we read the end */
- if (*cur != ':') {
- end = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("crashkernel: Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (end <= start) {
- pr_warn("crashkernel: end <= start\n");
- return -EINVAL;
- }
- }
-
- if (*cur != ':') {
- pr_warn("crashkernel: ':' expected\n");
- return -EINVAL;
- }
- cur++;
-
- size = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (size >= total_mem) {
- pr_warn("crashkernel: invalid size\n");
- return -EINVAL;
- }
-
- /* match ? */
- if (total_mem >= start && total_mem < end) {
- *crash_size = size;
- break;
- }
- } while (*cur++ == ',');
-
- if (*crash_size > 0) {
- while (*cur && *cur != ' ' && *cur != '@')
- cur++;
- if (*cur == '@') {
- cur++;
- *crash_base = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("Memory value expected after '@'\n");
- return -EINVAL;
- }
- }
- } else
- pr_info("crashkernel size resulted in zero bytes\n");
-
- return 0;
-}
-
-/*
- * That function parses "simple" (old) crashkernel command lines like
- *
- * crashkernel=size[@offset]
- *
- * It returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_simple(char *cmdline,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- char *cur = cmdline;
-
- *crash_size = memparse(cmdline, &cur);
- if (cmdline == cur) {
- pr_warn("crashkernel: memory value expected\n");
- return -EINVAL;
- }
-
- if (*cur == '@')
- *crash_base = memparse(cur+1, &cur);
- else if (*cur != ' ' && *cur != '\0') {
- pr_warn("crashkernel: unrecognized char: %c\n", *cur);
- return -EINVAL;
- }
-
- return 0;
-}
-
-#define SUFFIX_HIGH 0
-#define SUFFIX_LOW 1
-#define SUFFIX_NULL 2
-static __initdata char *suffix_tbl[] = {
- [SUFFIX_HIGH] = ",high",
- [SUFFIX_LOW] = ",low",
- [SUFFIX_NULL] = NULL,
-};
-
-/*
- * That function parses "suffix" crashkernel command lines like
- *
- * crashkernel=size,[high|low]
- *
- * It returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_suffix(char *cmdline,
- unsigned long long *crash_size,
- const char *suffix)
-{
- char *cur = cmdline;
-
- *crash_size = memparse(cmdline, &cur);
- if (cmdline == cur) {
- pr_warn("crashkernel: memory value expected\n");
- return -EINVAL;
- }
-
- /* check with suffix */
- if (strncmp(cur, suffix, strlen(suffix))) {
- pr_warn("crashkernel: unrecognized char: %c\n", *cur);
- return -EINVAL;
- }
- cur += strlen(suffix);
- if (*cur != ' ' && *cur != '\0') {
- pr_warn("crashkernel: unrecognized char: %c\n", *cur);
- return -EINVAL;
- }
-
- return 0;
-}
-
-static __init char *get_last_crashkernel(char *cmdline,
- const char *name,
- const char *suffix)
-{
- char *p = cmdline, *ck_cmdline = NULL;
-
- /* find crashkernel and use the last one if there are more */
- p = strstr(p, name);
- while (p) {
- char *end_p = strchr(p, ' ');
- char *q;
-
- if (!end_p)
- end_p = p + strlen(p);
-
- if (!suffix) {
- int i;
-
- /* skip the one with any known suffix */
- for (i = 0; suffix_tbl[i]; i++) {
- q = end_p - strlen(suffix_tbl[i]);
- if (!strncmp(q, suffix_tbl[i],
- strlen(suffix_tbl[i])))
- goto next;
- }
- ck_cmdline = p;
- } else {
- q = end_p - strlen(suffix);
- if (!strncmp(q, suffix, strlen(suffix)))
- ck_cmdline = p;
- }
-next:
- p = strstr(p+1, name);
- }
-
- return ck_cmdline;
-}
-
-static int __init __parse_crashkernel(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base,
- const char *suffix)
-{
- char *first_colon, *first_space;
- char *ck_cmdline;
- char *name = "crashkernel=";
-
- BUG_ON(!crash_size || !crash_base);
- *crash_size = 0;
- *crash_base = 0;
-
- ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
- if (!ck_cmdline)
- return -ENOENT;
-
- ck_cmdline += strlen(name);
-
- if (suffix)
- return parse_crashkernel_suffix(ck_cmdline, crash_size,
- suffix);
- /*
- * if the commandline contains a ':', then that's the extended
- * syntax -- if not, it must be the classic syntax
- */
- first_colon = strchr(ck_cmdline, ':');
- first_space = strchr(ck_cmdline, ' ');
- if (first_colon && (!first_space || first_colon < first_space))
- return parse_crashkernel_mem(ck_cmdline, system_ram,
- crash_size, crash_base);
-
- return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
-}
-
-/*
- * That function is the entry point for command line parsing and should be
- * called from the arch-specific code.
- *
- * If crashkernel=,high|low is supported on architecture, non-NULL values
- * should be passed to parameters 'low_size' and 'high'.
- */
-int __init parse_crashkernel(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base,
- unsigned long long *low_size,
- bool *high)
-{
- int ret;
-
- /* crashkernel=X[@offset] */
- ret = __parse_crashkernel(cmdline, system_ram, crash_size,
- crash_base, NULL);
-#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
- /*
- * If non-NULL 'high' passed in and no normal crashkernel
- * setting detected, try parsing crashkernel=,high|low.
- */
- if (high && ret == -ENOENT) {
- ret = __parse_crashkernel(cmdline, 0, crash_size,
- crash_base, suffix_tbl[SUFFIX_HIGH]);
- if (ret || !*crash_size)
- return -EINVAL;
-
- /*
- * crashkernel=Y,low can be specified or not, but invalid value
- * is not allowed.
- */
- ret = __parse_crashkernel(cmdline, 0, low_size,
- crash_base, suffix_tbl[SUFFIX_LOW]);
- if (ret == -ENOENT) {
- *low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
- ret = 0;
- } else if (ret) {
- return ret;
- }
-
- *high = true;
- }
-#endif
- if (!*crash_size)
- ret = -EINVAL;
-
- return ret;
-}
-
-/*
- * Add a dummy early_param handler to mark crashkernel= as a known command line
- * parameter and suppress incorrect warnings in init/main.c.
- */
-static int __init parse_crashkernel_dummy(char *arg)
-{
- return 0;
-}
-early_param("crashkernel", parse_crashkernel_dummy);
-
-#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
-static int __init reserve_crashkernel_low(unsigned long long low_size)
-{
-#ifdef CONFIG_64BIT
- unsigned long long low_base;
-
- low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
- if (!low_base) {
- pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
- return -ENOMEM;
- }
-
- pr_info("crashkernel low memory reserved: 0x%08llx - 0x%08llx (%lld MB)\n",
- low_base, low_base + low_size, low_size >> 20);
-
- crashk_low_res.start = low_base;
- crashk_low_res.end = low_base + low_size - 1;
-#endif
- return 0;
-}
-
-void __init reserve_crashkernel_generic(char *cmdline,
- unsigned long long crash_size,
- unsigned long long crash_base,
- unsigned long long crash_low_size,
- bool high)
-{
- unsigned long long search_end = CRASH_ADDR_LOW_MAX, search_base = 0;
- bool fixed_base = false;
-
- /* User specifies base address explicitly. */
- if (crash_base) {
- fixed_base = true;
- search_base = crash_base;
- search_end = crash_base + crash_size;
- } else if (high) {
- search_base = CRASH_ADDR_LOW_MAX;
- search_end = CRASH_ADDR_HIGH_MAX;
- }
-
-retry:
- crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
- search_base, search_end);
- if (!crash_base) {
- /*
- * For crashkernel=size[KMG]@offset[KMG], print out failure
- * message if can't reserve the specified region.
- */
- if (fixed_base) {
- pr_warn("crashkernel reservation failed - memory is in use.\n");
- return;
- }
-
- /*
- * For crashkernel=size[KMG], if the first attempt was for
- * low memory, fall back to high memory, the minimum required
- * low memory will be reserved later.
- */
- if (!high && search_end == CRASH_ADDR_LOW_MAX) {
- search_end = CRASH_ADDR_HIGH_MAX;
- search_base = CRASH_ADDR_LOW_MAX;
- crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
- goto retry;
- }
-
- /*
- * For crashkernel=size[KMG],high, if the first attempt was
- * for high memory, fall back to low memory.
- */
- if (high && search_end == CRASH_ADDR_HIGH_MAX) {
- search_end = CRASH_ADDR_LOW_MAX;
- search_base = 0;
- goto retry;
- }
- pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
- crash_size);
- return;
- }
-
- if ((crash_base >= CRASH_ADDR_LOW_MAX) &&
- crash_low_size && reserve_crashkernel_low(crash_low_size)) {
- memblock_phys_free(crash_base, crash_size);
- return;
- }
-
- pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
- crash_base, crash_base + crash_size, crash_size >> 20);
-
- /*
- * The crashkernel memory will be removed from the kernel linear
- * map. Inform kmemleak so that it won't try to access it.
- */
- kmemleak_ignore_phys(crash_base);
- if (crashk_low_res.end)
- kmemleak_ignore_phys(crashk_low_res.start);
-
- crashk_res.start = crash_base;
- crashk_res.end = crash_base + crash_size - 1;
-}
-
-static __init int insert_crashkernel_resources(void)
-{
- if (crashk_res.start < crashk_res.end)
- insert_resource(&iomem_resource, &crashk_res);
-
- if (crashk_low_res.start < crashk_low_res.end)
- insert_resource(&iomem_resource, &crashk_low_res);
-
- return 0;
-}
-early_initcall(insert_crashkernel_resources);
-#endif
-
int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
void **addr, unsigned long *sz)
{
diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c
new file mode 100644
index 000000000000..bbb6c3cb00e4
--- /dev/null
+++ b/kernel/crash_reserve.c
@@ -0,0 +1,464 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * crash.c - kernel crash support code.
+ * Copyright (C) 2002-2004 Eric Biederman <[email protected]>
+ */
+
+#include <linux/buildid.h>
+#include <linux/init.h>
+#include <linux/utsname.h>
+#include <linux/vmalloc.h>
+#include <linux/sizes.h>
+#include <linux/kexec.h>
+#include <linux/memory.h>
+#include <linux/cpuhotplug.h>
+#include <linux/memblock.h>
+#include <linux/kexec.h>
+#include <linux/kmemleak.h>
+
+#include <asm/page.h>
+#include <asm/sections.h>
+
+#include <crypto/sha1.h>
+
+#include "kallsyms_internal.h"
+#include "kexec_internal.h"
+
+/* Location of the reserved area for the crash kernel */
+struct resource crashk_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+ .desc = IORES_DESC_CRASH_KERNEL
+};
+struct resource crashk_low_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+ .desc = IORES_DESC_CRASH_KERNEL
+};
+
+/*
+ * parsing the "crashkernel" commandline
+ *
+ * this code is intended to be called from architecture specific code
+ */
+
+
+/*
+ * This function parses command lines in the format
+ *
+ * crashkernel=ramsize-range:size[,...][@offset]
+ *
+ * The function returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_mem(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ char *cur = cmdline, *tmp;
+ unsigned long long total_mem = system_ram;
+
+ /*
+ * Firmware sometimes reserves some memory regions for its own use,
+ * so the system memory size is less than the actual physical memory
+ * size. Work around this by rounding up the total size to 128M,
+ * which is enough for most test cases.
+ */
+ total_mem = roundup(total_mem, SZ_128M);
+
+ /* for each entry of the comma-separated list */
+ do {
+ unsigned long long start, end = ULLONG_MAX, size;
+
+ /* get the start of the range */
+ start = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("crashkernel: Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (*cur != '-') {
+ pr_warn("crashkernel: '-' expected\n");
+ return -EINVAL;
+ }
+ cur++;
+
+ /* if no ':' is here, than we read the end */
+ if (*cur != ':') {
+ end = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("crashkernel: Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (end <= start) {
+ pr_warn("crashkernel: end <= start\n");
+ return -EINVAL;
+ }
+ }
+
+ if (*cur != ':') {
+ pr_warn("crashkernel: ':' expected\n");
+ return -EINVAL;
+ }
+ cur++;
+
+ size = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (size >= total_mem) {
+ pr_warn("crashkernel: invalid size\n");
+ return -EINVAL;
+ }
+
+ /* match ? */
+ if (total_mem >= start && total_mem < end) {
+ *crash_size = size;
+ break;
+ }
+ } while (*cur++ == ',');
+
+ if (*crash_size > 0) {
+ while (*cur && *cur != ' ' && *cur != '@')
+ cur++;
+ if (*cur == '@') {
+ cur++;
+ *crash_base = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("Memory value expected after '@'\n");
+ return -EINVAL;
+ }
+ }
+ } else
+ pr_info("crashkernel size resulted in zero bytes\n");
+
+ return 0;
+}
+
+/*
+ * That function parses "simple" (old) crashkernel command lines like
+ *
+ * crashkernel=size[@offset]
+ *
+ * It returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_simple(char *cmdline,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ char *cur = cmdline;
+
+ *crash_size = memparse(cmdline, &cur);
+ if (cmdline == cur) {
+ pr_warn("crashkernel: memory value expected\n");
+ return -EINVAL;
+ }
+
+ if (*cur == '@')
+ *crash_base = memparse(cur+1, &cur);
+ else if (*cur != ' ' && *cur != '\0') {
+ pr_warn("crashkernel: unrecognized char: %c\n", *cur);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+#define SUFFIX_HIGH 0
+#define SUFFIX_LOW 1
+#define SUFFIX_NULL 2
+static __initdata char *suffix_tbl[] = {
+ [SUFFIX_HIGH] = ",high",
+ [SUFFIX_LOW] = ",low",
+ [SUFFIX_NULL] = NULL,
+};
+
+/*
+ * That function parses "suffix" crashkernel command lines like
+ *
+ * crashkernel=size,[high|low]
+ *
+ * It returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_suffix(char *cmdline,
+ unsigned long long *crash_size,
+ const char *suffix)
+{
+ char *cur = cmdline;
+
+ *crash_size = memparse(cmdline, &cur);
+ if (cmdline == cur) {
+ pr_warn("crashkernel: memory value expected\n");
+ return -EINVAL;
+ }
+
+ /* check with suffix */
+ if (strncmp(cur, suffix, strlen(suffix))) {
+ pr_warn("crashkernel: unrecognized char: %c\n", *cur);
+ return -EINVAL;
+ }
+ cur += strlen(suffix);
+ if (*cur != ' ' && *cur != '\0') {
+ pr_warn("crashkernel: unrecognized char: %c\n", *cur);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static __init char *get_last_crashkernel(char *cmdline,
+ const char *name,
+ const char *suffix)
+{
+ char *p = cmdline, *ck_cmdline = NULL;
+
+ /* find crashkernel and use the last one if there are more */
+ p = strstr(p, name);
+ while (p) {
+ char *end_p = strchr(p, ' ');
+ char *q;
+
+ if (!end_p)
+ end_p = p + strlen(p);
+
+ if (!suffix) {
+ int i;
+
+ /* skip the one with any known suffix */
+ for (i = 0; suffix_tbl[i]; i++) {
+ q = end_p - strlen(suffix_tbl[i]);
+ if (!strncmp(q, suffix_tbl[i],
+ strlen(suffix_tbl[i])))
+ goto next;
+ }
+ ck_cmdline = p;
+ } else {
+ q = end_p - strlen(suffix);
+ if (!strncmp(q, suffix, strlen(suffix)))
+ ck_cmdline = p;
+ }
+next:
+ p = strstr(p+1, name);
+ }
+
+ return ck_cmdline;
+}
+
+static int __init __parse_crashkernel(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base,
+ const char *suffix)
+{
+ char *first_colon, *first_space;
+ char *ck_cmdline;
+ char *name = "crashkernel=";
+
+ BUG_ON(!crash_size || !crash_base);
+ *crash_size = 0;
+ *crash_base = 0;
+
+ ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
+ if (!ck_cmdline)
+ return -ENOENT;
+
+ ck_cmdline += strlen(name);
+
+ if (suffix)
+ return parse_crashkernel_suffix(ck_cmdline, crash_size,
+ suffix);
+ /*
+ * if the commandline contains a ':', then that's the extended
+ * syntax -- if not, it must be the classic syntax
+ */
+ first_colon = strchr(ck_cmdline, ':');
+ first_space = strchr(ck_cmdline, ' ');
+ if (first_colon && (!first_space || first_colon < first_space))
+ return parse_crashkernel_mem(ck_cmdline, system_ram,
+ crash_size, crash_base);
+
+ return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
+}
+
+/*
+ * That function is the entry point for command line parsing and should be
+ * called from the arch-specific code.
+ *
+ * If crashkernel=,high|low is supported on architecture, non-NULL values
+ * should be passed to parameters 'low_size' and 'high'.
+ */
+int __init parse_crashkernel(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base,
+ unsigned long long *low_size,
+ bool *high)
+{
+ int ret;
+
+ /* crashkernel=X[@offset] */
+ ret = __parse_crashkernel(cmdline, system_ram, crash_size,
+ crash_base, NULL);
+#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
+ /*
+ * If non-NULL 'high' passed in and no normal crashkernel
+ * setting detected, try parsing crashkernel=,high|low.
+ */
+ if (high && ret == -ENOENT) {
+ ret = __parse_crashkernel(cmdline, 0, crash_size,
+ crash_base, suffix_tbl[SUFFIX_HIGH]);
+ if (ret || !*crash_size)
+ return -EINVAL;
+
+ /*
+ * crashkernel=Y,low can be specified or not, but invalid value
+ * is not allowed.
+ */
+ ret = __parse_crashkernel(cmdline, 0, low_size,
+ crash_base, suffix_tbl[SUFFIX_LOW]);
+ if (ret == -ENOENT) {
+ *low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ ret = 0;
+ } else if (ret) {
+ return ret;
+ }
+
+ *high = true;
+ }
+#endif
+ if (!*crash_size)
+ ret = -EINVAL;
+
+ return ret;
+}
+
+/*
+ * Add a dummy early_param handler to mark crashkernel= as a known command line
+ * parameter and suppress incorrect warnings in init/main.c.
+ */
+static int __init parse_crashkernel_dummy(char *arg)
+{
+ return 0;
+}
+early_param("crashkernel", parse_crashkernel_dummy);
+
+#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
+static int __init reserve_crashkernel_low(unsigned long long low_size)
+{
+#ifdef CONFIG_64BIT
+ unsigned long long low_base;
+
+ low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
+ if (!low_base) {
+ pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
+ return -ENOMEM;
+ }
+
+ pr_info("crashkernel low memory reserved: 0x%08llx - 0x%08llx (%lld MB)\n",
+ low_base, low_base + low_size, low_size >> 20);
+
+ crashk_low_res.start = low_base;
+ crashk_low_res.end = low_base + low_size - 1;
+ insert_resource(&iomem_resource, &crashk_low_res);
+#endif
+ return 0;
+}
+
+void __init reserve_crashkernel_generic(char *cmdline,
+ unsigned long long crash_size,
+ unsigned long long crash_base,
+ unsigned long long crash_low_size,
+ bool high)
+{
+ unsigned long long search_end = CRASH_ADDR_LOW_MAX, search_base = 0;
+ bool fixed_base = false;
+
+ /* User specifies base address explicitly. */
+ if (crash_base) {
+ fixed_base = true;
+ search_base = crash_base;
+ search_end = crash_base + crash_size;
+ } else if (high) {
+ search_base = CRASH_ADDR_LOW_MAX;
+ search_end = CRASH_ADDR_HIGH_MAX;
+ }
+
+retry:
+ crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
+ search_base, search_end);
+ if (!crash_base) {
+ /*
+ * For crashkernel=size[KMG]@offset[KMG], print out failure
+ * message if can't reserve the specified region.
+ */
+ if (fixed_base) {
+ pr_warn("crashkernel reservation failed - memory is in use.\n");
+ return;
+ }
+
+ /*
+ * For crashkernel=size[KMG], if the first attempt was for
+ * low memory, fall back to high memory, the minimum required
+ * low memory will be reserved later.
+ */
+ if (!high && search_end == CRASH_ADDR_LOW_MAX) {
+ search_end = CRASH_ADDR_HIGH_MAX;
+ search_base = CRASH_ADDR_LOW_MAX;
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ goto retry;
+ }
+
+ /*
+ * For crashkernel=size[KMG],high, if the first attempt was
+ * for high memory, fall back to low memory.
+ */
+ if (high && search_end == CRASH_ADDR_HIGH_MAX) {
+ search_end = CRASH_ADDR_LOW_MAX;
+ search_base = 0;
+ goto retry;
+ }
+ pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
+ crash_size);
+ return;
+ }
+
+ if ((crash_base >= CRASH_ADDR_LOW_MAX) &&
+ crash_low_size && reserve_crashkernel_low(crash_low_size)) {
+ memblock_phys_free(crash_base, crash_size);
+ return;
+ }
+
+ pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
+ crash_base, crash_base + crash_size, crash_size >> 20);
+
+ /*
+ * The crashkernel memory will be removed from the kernel linear
+ * map. Inform kmemleak so that it won't try to access it.
+ */
+ kmemleak_ignore_phys(crash_base);
+ if (crashk_low_res.end)
+ kmemleak_ignore_phys(crashk_low_res.start);
+
+ crashk_res.start = crash_base;
+ crashk_res.end = crash_base + crash_size - 1;
+}
+
+static __init int insert_crashkernel_resources(void)
+{
+ if (crashk_res.start < crashk_res.end)
+ insert_resource(&iomem_resource, &crashk_res);
+
+ if (crashk_low_res.start < crashk_low_res.end)
+ insert_resource(&iomem_resource, &crashk_low_res);
+
+ return 0;
+}
+early_initcall(insert_crashkernel_resources);
+#endif
--
2.41.0


2024-01-24 05:14:23

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 04/14] crash: split crash dumping code out from kexec_core.c

Currently, KEXEC_CORE select CRASH_CORE automatically because crash codes
need be built in to avoid compiling error when building kexec code even
though the crash dumping functionality is not enabled. E.g
--------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_KEXEC=y
CONFIG_KEXEC_FILE=y
---------------------

After splitting out crashkernel reservation code and vmcoreinfo exporting
code, there's only crash related code left in kernel/crash_core.c. Now
move crash related codes from kexec_core.c to crash_core.c and only build it
in when CONFIG_CRASH_DUMP=y.

And also wrap up crash codes inside CONFIG_CRASH_DUMP ifdeffery scope,
or replace inappropriate CONFIG_KEXEC_CORE ifdef with CONFIG_CRASH_DUMP
ifdef in generic kernel files.

With these changes, crash_core codes are abstracted from kexec codes and
can be disabled at all if only kexec reboot feature is wanted.

Signed-off-by: Baoquan He <[email protected]>
---
drivers/base/cpu.c | 6 +-
include/linux/crash_core.h | 61 +++++++++
include/linux/kexec.h | 45 +------
init/initramfs.c | 2 +-
kernel/Makefile | 3 +-
kernel/crash_core.c | 256 +++++++++++++++++++++++++++++++++++++
kernel/kexec.c | 11 +-
kernel/kexec_core.c | 250 ++----------------------------------
kernel/kexec_file.c | 13 +-
kernel/ksysfs.c | 4 +
10 files changed, 359 insertions(+), 292 deletions(-)

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 47de0f140ba6..b621a0fc75e1 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -144,7 +144,7 @@ static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store);
#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
#endif /* CONFIG_HOTPLUG_CPU */

-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
#include <linux/kexec.h>

static ssize_t crash_notes_show(struct device *dev,
@@ -189,14 +189,14 @@ static const struct attribute_group crash_note_cpu_attr_group = {
#endif

static const struct attribute_group *common_cpu_attr_groups[] = {
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
&crash_note_cpu_attr_group,
#endif
NULL
};

static const struct attribute_group *hotplugable_cpu_attr_groups[] = {
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
&crash_note_cpu_attr_group,
#endif
NULL
diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
index 7f19f62018ef..23270b16e1db 100644
--- a/include/linux/crash_core.h
+++ b/include/linux/crash_core.h
@@ -6,6 +6,48 @@
#include <linux/elfcore.h>
#include <linux/elf.h>

+struct kimage;
+
+#ifdef CONFIG_CRASH_DUMP
+
+int crash_shrink_memory(unsigned long new_size);
+ssize_t crash_get_memory_size(void);
+
+#ifndef arch_kexec_protect_crashkres
+/*
+ * Protection mechanism for crashkernel reserved memory after
+ * the kdump kernel is loaded.
+ *
+ * Provide an empty default implementation here -- architecture
+ * code may override this
+ */
+static inline void arch_kexec_protect_crashkres(void) { }
+#endif
+
+#ifndef arch_kexec_unprotect_crashkres
+static inline void arch_kexec_unprotect_crashkres(void) { }
+#endif
+
+
+
+#ifndef arch_crash_handle_hotplug_event
+static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
+#endif
+
+int crash_check_update_elfcorehdr(void);
+
+#ifndef crash_hotplug_cpu_support
+static inline int crash_hotplug_cpu_support(void) { return 0; }
+#endif
+
+#ifndef crash_hotplug_memory_support
+static inline int crash_hotplug_memory_support(void) { return 0; }
+#endif
+
+#ifndef crash_get_elfcorehdr_size
+static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
+#endif
+
/* Alignment required for elf header segment */
#define ELF_CORE_HEADER_ALIGN 4096

@@ -31,4 +73,23 @@ struct kexec_segment;
#define KEXEC_CRASH_HP_REMOVE_MEMORY 4
#define KEXEC_CRASH_HP_INVALID_CPU -1U

+extern void __crash_kexec(struct pt_regs *regs);
+extern void crash_kexec(struct pt_regs *regs);
+int kexec_should_crash(struct task_struct *p);
+int kexec_crash_loaded(void);
+void crash_save_cpu(struct pt_regs *regs, int cpu);
+extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
+
+#else /* !CONFIG_CRASH_DUMP*/
+struct pt_regs;
+struct task_struct;
+struct kimage;
+static inline void __crash_kexec(struct pt_regs *regs) { }
+static inline void crash_kexec(struct pt_regs *regs) { }
+static inline int kexec_should_crash(struct task_struct *p) { return 0; }
+static inline int kexec_crash_loaded(void) { return 0; }
+static inline void crash_save_cpu(struct pt_regs *regs, int cpu) {};
+static inline int kimage_crash_copy_vmcoreinfo(struct kimage *image) { return 0; };
+#endif /* CONFIG_CRASH_DUMP*/
+
#endif /* LINUX_CRASH_CORE_H */
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 9c7bb8b56ed6..060835bb82d5 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -15,7 +15,6 @@

#if !defined(__ASSEMBLY__)

-#include <linux/crash_core.h>
#include <linux/vmcore_info.h>
#include <linux/crash_reserve.h>
#include <asm/io.h>
@@ -33,6 +32,7 @@ extern note_buf_t __percpu *crash_notes;
#include <linux/module.h>
#include <linux/highmem.h>
#include <asm/kexec.h>
+#include <linux/crash_core.h>

/* Verify architecture specific macros are defined */

@@ -380,13 +380,6 @@ extern struct page *kimage_alloc_control_pages(struct kimage *image,
static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
#endif

-extern void __crash_kexec(struct pt_regs *);
-extern void crash_kexec(struct pt_regs *);
-int kexec_should_crash(struct task_struct *);
-int kexec_crash_loaded(void);
-void crash_save_cpu(struct pt_regs *regs, int cpu);
-extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
-
extern struct kimage *kexec_image;
extern struct kimage *kexec_crash_image;

@@ -410,24 +403,6 @@ bool kexec_load_permitted(int kexec_image_type);
/* flag to track if kexec reboot is in progress */
extern bool kexec_in_progress;

-int crash_shrink_memory(unsigned long new_size);
-ssize_t crash_get_memory_size(void);
-
-#ifndef arch_kexec_protect_crashkres
-/*
- * Protection mechanism for crashkernel reserved memory after
- * the kdump kernel is loaded.
- *
- * Provide an empty default implementation here -- architecture
- * code may override this
- */
-static inline void arch_kexec_protect_crashkres(void) { }
-#endif
-
-#ifndef arch_kexec_unprotect_crashkres
-static inline void arch_kexec_unprotect_crashkres(void) { }
-#endif
-
#ifndef page_to_boot_pfn
static inline unsigned long page_to_boot_pfn(struct page *page)
{
@@ -484,24 +459,6 @@ static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, g
static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
#endif

-#ifndef arch_crash_handle_hotplug_event
-static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
-#endif
-
-int crash_check_update_elfcorehdr(void);
-
-#ifndef crash_hotplug_cpu_support
-static inline int crash_hotplug_cpu_support(void) { return 0; }
-#endif
-
-#ifndef crash_hotplug_memory_support
-static inline int crash_hotplug_memory_support(void) { return 0; }
-#endif
-
-#ifndef crash_get_elfcorehdr_size
-static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
-#endif
-
extern bool kexec_file_dbg_print;

#define kexec_dprintk(fmt, ...) \
diff --git a/init/initramfs.c b/init/initramfs.c
index d3c623dde01a..70cdefa0911b 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -642,7 +642,7 @@ void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
"initrd");
}

-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_RESERVE
static bool __init kexec_free_initrd(void)
{
unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
diff --git a/kernel/Makefile b/kernel/Makefile
index 35abc65e1f1a..3c13240dfc9f 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -70,7 +70,8 @@ obj-$(CONFIG_KALLSYMS_SELFTEST) += kallsyms_selftest.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_VMCORE_INFO) += vmcore_info.o elfcorehdr.o
obj-$(CONFIG_CRASH_RESERVE) += crash_reserve.o
-obj-$(CONFIG_KEXEC_CORE) += kexec_core.o crash_core.o
+obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
+obj-$(CONFIG_CRASH_DUMP) += crash_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_KEXEC_ELF) += kexec_elf.o
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 2f4df1fe6f7a..78b5dc7cee3a 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -11,9 +11,14 @@
#include <linux/sizes.h>
#include <linux/kexec.h>
#include <linux/memory.h>
+#include <linux/mm.h>
#include <linux/cpuhotplug.h>
#include <linux/memblock.h>
#include <linux/kmemleak.h>
+#include <linux/crash_core.h>
+#include <linux/reboot.h>
+#include <linux/btf.h>
+#include <linux/objtool.h>

#include <asm/page.h>
#include <asm/sections.h>
@@ -26,6 +31,131 @@
/* Per cpu memory for storing cpu states in case of system crash. */
note_buf_t __percpu *crash_notes;

+#ifdef CONFIG_CRASH_DUMP
+
+int kimage_crash_copy_vmcoreinfo(struct kimage *image)
+{
+ struct page *vmcoreinfo_page;
+ void *safecopy;
+
+ if (!IS_ENABLED(CONFIG_CRASH_DUMP))
+ return 0;
+ if (image->type != KEXEC_TYPE_CRASH)
+ return 0;
+
+ /*
+ * For kdump, allocate one vmcoreinfo safe copy from the
+ * crash memory. as we have arch_kexec_protect_crashkres()
+ * after kexec syscall, we naturally protect it from write
+ * (even read) access under kernel direct mapping. But on
+ * the other hand, we still need to operate it when crash
+ * happens to generate vmcoreinfo note, hereby we rely on
+ * vmap for this purpose.
+ */
+ vmcoreinfo_page = kimage_alloc_control_pages(image, 0);
+ if (!vmcoreinfo_page) {
+ pr_warn("Could not allocate vmcoreinfo buffer\n");
+ return -ENOMEM;
+ }
+ safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL);
+ if (!safecopy) {
+ pr_warn("Could not vmap vmcoreinfo buffer\n");
+ return -ENOMEM;
+ }
+
+ image->vmcoreinfo_data_copy = safecopy;
+ crash_update_vmcoreinfo_safecopy(safecopy);
+
+ return 0;
+}
+
+
+
+int kexec_should_crash(struct task_struct *p)
+{
+ /*
+ * If crash_kexec_post_notifiers is enabled, don't run
+ * crash_kexec() here yet, which must be run after panic
+ * notifiers in panic().
+ */
+ if (crash_kexec_post_notifiers)
+ return 0;
+ /*
+ * There are 4 panic() calls in make_task_dead() path, each of which
+ * corresponds to each of these 4 conditions.
+ */
+ if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
+ return 1;
+ return 0;
+}
+
+int kexec_crash_loaded(void)
+{
+ return !!kexec_crash_image;
+}
+EXPORT_SYMBOL_GPL(kexec_crash_loaded);
+
+/*
+ * No panic_cpu check version of crash_kexec(). This function is called
+ * only when panic_cpu holds the current CPU number; this is the only CPU
+ * which processes crash_kexec routines.
+ */
+void __noclone __crash_kexec(struct pt_regs *regs)
+{
+ /* Take the kexec_lock here to prevent sys_kexec_load
+ * running on one cpu from replacing the crash kernel
+ * we are using after a panic on a different cpu.
+ *
+ * If the crash kernel was not located in a fixed area
+ * of memory the xchg(&kexec_crash_image) would be
+ * sufficient. But since I reuse the memory...
+ */
+ if (kexec_trylock()) {
+ if (kexec_crash_image) {
+ struct pt_regs fixed_regs;
+
+ crash_setup_regs(&fixed_regs, regs);
+ crash_save_vmcoreinfo();
+ machine_crash_shutdown(&fixed_regs);
+ machine_kexec(kexec_crash_image);
+ }
+ kexec_unlock();
+ }
+}
+STACK_FRAME_NON_STANDARD(__crash_kexec);
+
+__bpf_kfunc void crash_kexec(struct pt_regs *regs)
+{
+ int old_cpu, this_cpu;
+
+ /*
+ * Only one CPU is allowed to execute the crash_kexec() code as with
+ * panic(). Otherwise parallel calls of panic() and crash_kexec()
+ * may stop each other. To exclude them, we use panic_cpu here too.
+ */
+ old_cpu = PANIC_CPU_INVALID;
+ this_cpu = raw_smp_processor_id();
+
+ if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) {
+ /* This is the 1st CPU which comes here, so go ahead. */
+ __crash_kexec(regs);
+
+ /*
+ * Reset panic_cpu to allow another panic()/crash_kexec()
+ * call.
+ */
+ atomic_set(&panic_cpu, PANIC_CPU_INVALID);
+ }
+}
+
+static inline resource_size_t crash_resource_size(const struct resource *res)
+{
+ return !res->end ? 0 : resource_size(res);
+}
+
+
+
+
int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
void **addr, unsigned long *sz)
{
@@ -187,6 +317,130 @@ int crash_exclude_mem_range(struct crash_mem *mem,
return 0;
}

+ssize_t crash_get_memory_size(void)
+{
+ ssize_t size = 0;
+
+ if (!kexec_trylock())
+ return -EBUSY;
+
+ size += crash_resource_size(&crashk_res);
+ size += crash_resource_size(&crashk_low_res);
+
+ kexec_unlock();
+ return size;
+}
+
+static int __crash_shrink_memory(struct resource *old_res,
+ unsigned long new_size)
+{
+ struct resource *ram_res;
+
+ ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
+ if (!ram_res)
+ return -ENOMEM;
+
+ ram_res->start = old_res->start + new_size;
+ ram_res->end = old_res->end;
+ ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
+ ram_res->name = "System RAM";
+
+ if (!new_size) {
+ release_resource(old_res);
+ old_res->start = 0;
+ old_res->end = 0;
+ } else {
+ crashk_res.end = ram_res->start - 1;
+ }
+
+ crash_free_reserved_phys_range(ram_res->start, ram_res->end);
+ insert_resource(&iomem_resource, ram_res);
+
+ return 0;
+}
+
+int crash_shrink_memory(unsigned long new_size)
+{
+ int ret = 0;
+ unsigned long old_size, low_size;
+
+ if (!kexec_trylock())
+ return -EBUSY;
+
+ if (kexec_crash_image) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+
+ low_size = crash_resource_size(&crashk_low_res);
+ old_size = crash_resource_size(&crashk_res) + low_size;
+ new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
+ if (new_size >= old_size) {
+ ret = (new_size == old_size) ? 0 : -EINVAL;
+ goto unlock;
+ }
+
+ /*
+ * (low_size > new_size) implies that low_size is greater than zero.
+ * This also means that if low_size is zero, the else branch is taken.
+ *
+ * If low_size is greater than 0, (low_size > new_size) indicates that
+ * crashk_low_res also needs to be shrunken. Otherwise, only crashk_res
+ * needs to be shrunken.
+ */
+ if (low_size > new_size) {
+ ret = __crash_shrink_memory(&crashk_res, 0);
+ if (ret)
+ goto unlock;
+
+ ret = __crash_shrink_memory(&crashk_low_res, new_size);
+ } else {
+ ret = __crash_shrink_memory(&crashk_res, new_size - low_size);
+ }
+
+ /* Swap crashk_res and crashk_low_res if needed */
+ if (!crashk_res.end && crashk_low_res.end) {
+ crashk_res.start = crashk_low_res.start;
+ crashk_res.end = crashk_low_res.end;
+ release_resource(&crashk_low_res);
+ crashk_low_res.start = 0;
+ crashk_low_res.end = 0;
+ insert_resource(&iomem_resource, &crashk_res);
+ }
+
+unlock:
+ kexec_unlock();
+ return ret;
+}
+
+void crash_save_cpu(struct pt_regs *regs, int cpu)
+{
+ struct elf_prstatus prstatus;
+ u32 *buf;
+
+ if ((cpu < 0) || (cpu >= nr_cpu_ids))
+ return;
+
+ /* Using ELF notes here is opportunistic.
+ * I need a well defined structure format
+ * for the data I pass, and I need tags
+ * on the data to indicate what information I have
+ * squirrelled away. ELF notes happen to provide
+ * all of that, so there is no need to invent something new.
+ */
+ buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
+ if (!buf)
+ return;
+ memset(&prstatus, 0, sizeof(prstatus));
+ prstatus.common.pr_pid = current->pid;
+ elf_core_copy_regs(&prstatus.pr_reg, regs);
+ buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
+ &prstatus, sizeof(prstatus));
+ final_note(buf);
+}
+
+
+
static int __init crash_notes_memory_init(void)
{
/* Allocate memory for saving cpu registers. */
@@ -220,6 +474,8 @@ static int __init crash_notes_memory_init(void)
}
subsys_initcall(crash_notes_memory_init);

+#endif /*CONFIG_CRASH_DUMP*/
+
#ifdef CONFIG_CRASH_HOTPLUG
#undef pr_fmt
#define pr_fmt(fmt) "crash hp: " fmt
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 8f35a5a42af8..bab542fc1463 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -28,12 +28,14 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
struct kimage *image;
bool kexec_on_panic = flags & KEXEC_ON_CRASH;

+#ifdef CONFIG_CRASH_DUMP
if (kexec_on_panic) {
/* Verify we have a valid entry point */
if ((entry < phys_to_boot_phys(crashk_res.start)) ||
(entry > phys_to_boot_phys(crashk_res.end)))
return -EADDRNOTAVAIL;
}
+#endif

/* Allocate and initialize a controlling structure */
image = do_kimage_alloc_init();
@@ -44,11 +46,13 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
image->nr_segments = nr_segments;
memcpy(image->segment, segments, nr_segments * sizeof(*segments));

+#ifdef CONFIG_CRASH_DUMP
if (kexec_on_panic) {
/* Enable special crash kernel control page alloc policy. */
image->control_page = crashk_res.start;
image->type = KEXEC_TYPE_CRASH;
}
+#endif

ret = sanity_check_segment_list(image);
if (ret)
@@ -99,13 +103,14 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
if (!kexec_trylock())
return -EBUSY;

+#ifdef CONFIG_CRASH_DUMP
if (flags & KEXEC_ON_CRASH) {
dest_image = &kexec_crash_image;
if (kexec_crash_image)
arch_kexec_unprotect_crashkres();
- } else {
+ } else
+#endif
dest_image = &kexec_image;
- }

if (nr_segments == 0) {
/* Uninstall image */
@@ -162,8 +167,10 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
image = xchg(dest_image, image);

out:
+#ifdef CONFIG_CRASH_DUMP
if ((flags & KEXEC_ON_CRASH) && kexec_crash_image)
arch_kexec_protect_crashkres();
+#endif

kimage_free(image);
out_unlock:
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index d08fc7b5db97..ce3429e7972c 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -54,30 +54,6 @@ bool kexec_in_progress = false;

bool kexec_file_dbg_print;

-int kexec_should_crash(struct task_struct *p)
-{
- /*
- * If crash_kexec_post_notifiers is enabled, don't run
- * crash_kexec() here yet, which must be run after panic
- * notifiers in panic().
- */
- if (crash_kexec_post_notifiers)
- return 0;
- /*
- * There are 4 panic() calls in make_task_dead() path, each of which
- * corresponds to each of these 4 conditions.
- */
- if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
- return 1;
- return 0;
-}
-
-int kexec_crash_loaded(void)
-{
- return !!kexec_crash_image;
-}
-EXPORT_SYMBOL_GPL(kexec_crash_loaded);
-
/*
* When kexec transitions to the new kernel there is a one-to-one
* mapping between physical and virtual addresses. On processors
@@ -209,6 +185,7 @@ int sanity_check_segment_list(struct kimage *image)
if (total_pages > nr_pages / 2)
return -EINVAL;

+#ifdef CONFIG_CRASH_DUMP
/*
* Verify we have good destination addresses. Normally
* the caller is responsible for making certain we don't
@@ -231,6 +208,7 @@ int sanity_check_segment_list(struct kimage *image)
return -EADDRNOTAVAIL;
}
}
+#endif

return 0;
}
@@ -403,6 +381,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
return pages;
}

+#ifdef CONFIG_CRASH_DUMP
static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
unsigned int order)
{
@@ -468,6 +447,7 @@ static struct page *kimage_alloc_crash_control_pages(struct kimage *image,

return pages;
}
+#endif


struct page *kimage_alloc_control_pages(struct kimage *image,
@@ -479,48 +459,16 @@ struct page *kimage_alloc_control_pages(struct kimage *image,
case KEXEC_TYPE_DEFAULT:
pages = kimage_alloc_normal_control_pages(image, order);
break;
+#ifdef CONFIG_CRASH_DUMP
case KEXEC_TYPE_CRASH:
pages = kimage_alloc_crash_control_pages(image, order);
break;
+#endif
}

return pages;
}

-int kimage_crash_copy_vmcoreinfo(struct kimage *image)
-{
- struct page *vmcoreinfo_page;
- void *safecopy;
-
- if (image->type != KEXEC_TYPE_CRASH)
- return 0;
-
- /*
- * For kdump, allocate one vmcoreinfo safe copy from the
- * crash memory. as we have arch_kexec_protect_crashkres()
- * after kexec syscall, we naturally protect it from write
- * (even read) access under kernel direct mapping. But on
- * the other hand, we still need to operate it when crash
- * happens to generate vmcoreinfo note, hereby we rely on
- * vmap for this purpose.
- */
- vmcoreinfo_page = kimage_alloc_control_pages(image, 0);
- if (!vmcoreinfo_page) {
- pr_warn("Could not allocate vmcoreinfo buffer\n");
- return -ENOMEM;
- }
- safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL);
- if (!safecopy) {
- pr_warn("Could not vmap vmcoreinfo buffer\n");
- return -ENOMEM;
- }
-
- image->vmcoreinfo_data_copy = safecopy;
- crash_update_vmcoreinfo_safecopy(safecopy);
-
- return 0;
-}
-
static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
{
if (*image->entry != 0)
@@ -603,10 +551,12 @@ void kimage_free(struct kimage *image)
if (!image)
return;

+#ifdef CONFIG_CRASH_DUMP
if (image->vmcoreinfo_data_copy) {
crash_update_vmcoreinfo_safecopy(NULL);
vunmap(image->vmcoreinfo_data_copy);
}
+#endif

kimage_free_extra_pages(image);
for_each_kimage_entry(image, ptr, entry) {
@@ -824,6 +774,7 @@ static int kimage_load_normal_segment(struct kimage *image,
return result;
}

+#ifdef CONFIG_CRASH_DUMP
static int kimage_load_crash_segment(struct kimage *image,
struct kexec_segment *segment)
{
@@ -891,6 +842,7 @@ static int kimage_load_crash_segment(struct kimage *image,
out:
return result;
}
+#endif

int kimage_load_segment(struct kimage *image,
struct kexec_segment *segment)
@@ -901,9 +853,11 @@ int kimage_load_segment(struct kimage *image,
case KEXEC_TYPE_DEFAULT:
result = kimage_load_normal_segment(image, segment);
break;
+#ifdef CONFIG_CRASH_DUMP
case KEXEC_TYPE_CRASH:
result = kimage_load_crash_segment(image, segment);
break;
+#endif
}

return result;
@@ -1027,186 +981,6 @@ bool kexec_load_permitted(int kexec_image_type)
return true;
}

-/*
- * No panic_cpu check version of crash_kexec(). This function is called
- * only when panic_cpu holds the current CPU number; this is the only CPU
- * which processes crash_kexec routines.
- */
-void __noclone __crash_kexec(struct pt_regs *regs)
-{
- /* Take the kexec_lock here to prevent sys_kexec_load
- * running on one cpu from replacing the crash kernel
- * we are using after a panic on a different cpu.
- *
- * If the crash kernel was not located in a fixed area
- * of memory the xchg(&kexec_crash_image) would be
- * sufficient. But since I reuse the memory...
- */
- if (kexec_trylock()) {
- if (kexec_crash_image) {
- struct pt_regs fixed_regs;
-
- crash_setup_regs(&fixed_regs, regs);
- crash_save_vmcoreinfo();
- machine_crash_shutdown(&fixed_regs);
- machine_kexec(kexec_crash_image);
- }
- kexec_unlock();
- }
-}
-STACK_FRAME_NON_STANDARD(__crash_kexec);
-
-__bpf_kfunc void crash_kexec(struct pt_regs *regs)
-{
- int old_cpu, this_cpu;
-
- /*
- * Only one CPU is allowed to execute the crash_kexec() code as with
- * panic(). Otherwise parallel calls of panic() and crash_kexec()
- * may stop each other. To exclude them, we use panic_cpu here too.
- */
- old_cpu = PANIC_CPU_INVALID;
- this_cpu = raw_smp_processor_id();
-
- if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) {
- /* This is the 1st CPU which comes here, so go ahead. */
- __crash_kexec(regs);
-
- /*
- * Reset panic_cpu to allow another panic()/crash_kexec()
- * call.
- */
- atomic_set(&panic_cpu, PANIC_CPU_INVALID);
- }
-}
-
-static inline resource_size_t crash_resource_size(const struct resource *res)
-{
- return !res->end ? 0 : resource_size(res);
-}
-
-ssize_t crash_get_memory_size(void)
-{
- ssize_t size = 0;
-
- if (!kexec_trylock())
- return -EBUSY;
-
- size += crash_resource_size(&crashk_res);
- size += crash_resource_size(&crashk_low_res);
-
- kexec_unlock();
- return size;
-}
-
-static int __crash_shrink_memory(struct resource *old_res,
- unsigned long new_size)
-{
- struct resource *ram_res;
-
- ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
- if (!ram_res)
- return -ENOMEM;
-
- ram_res->start = old_res->start + new_size;
- ram_res->end = old_res->end;
- ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
- ram_res->name = "System RAM";
-
- if (!new_size) {
- release_resource(old_res);
- old_res->start = 0;
- old_res->end = 0;
- } else {
- crashk_res.end = ram_res->start - 1;
- }
-
- crash_free_reserved_phys_range(ram_res->start, ram_res->end);
- insert_resource(&iomem_resource, ram_res);
-
- return 0;
-}
-
-int crash_shrink_memory(unsigned long new_size)
-{
- int ret = 0;
- unsigned long old_size, low_size;
-
- if (!kexec_trylock())
- return -EBUSY;
-
- if (kexec_crash_image) {
- ret = -ENOENT;
- goto unlock;
- }
-
- low_size = crash_resource_size(&crashk_low_res);
- old_size = crash_resource_size(&crashk_res) + low_size;
- new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
- if (new_size >= old_size) {
- ret = (new_size == old_size) ? 0 : -EINVAL;
- goto unlock;
- }
-
- /*
- * (low_size > new_size) implies that low_size is greater than zero.
- * This also means that if low_size is zero, the else branch is taken.
- *
- * If low_size is greater than 0, (low_size > new_size) indicates that
- * crashk_low_res also needs to be shrunken. Otherwise, only crashk_res
- * needs to be shrunken.
- */
- if (low_size > new_size) {
- ret = __crash_shrink_memory(&crashk_res, 0);
- if (ret)
- goto unlock;
-
- ret = __crash_shrink_memory(&crashk_low_res, new_size);
- } else {
- ret = __crash_shrink_memory(&crashk_res, new_size - low_size);
- }
-
- /* Swap crashk_res and crashk_low_res if needed */
- if (!crashk_res.end && crashk_low_res.end) {
- crashk_res.start = crashk_low_res.start;
- crashk_res.end = crashk_low_res.end;
- release_resource(&crashk_low_res);
- crashk_low_res.start = 0;
- crashk_low_res.end = 0;
- insert_resource(&iomem_resource, &crashk_res);
- }
-
-unlock:
- kexec_unlock();
- return ret;
-}
-
-void crash_save_cpu(struct pt_regs *regs, int cpu)
-{
- struct elf_prstatus prstatus;
- u32 *buf;
-
- if ((cpu < 0) || (cpu >= nr_cpu_ids))
- return;
-
- /* Using ELF notes here is opportunistic.
- * I need a well defined structure format
- * for the data I pass, and I need tags
- * on the data to indicate what information I have
- * squirrelled away. ELF notes happen to provide
- * all of that, so there is no need to invent something new.
- */
- buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
- if (!buf)
- return;
- memset(&prstatus, 0, sizeof(prstatus));
- prstatus.common.pr_pid = current->pid;
- elf_core_copy_regs(&prstatus.pr_reg, regs);
- buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
- &prstatus, sizeof(prstatus));
- final_note(buf);
-}
-
/*
* Move into place and start executing a preloaded standalone
* executable. If nothing was preloaded return an error.
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index bef2f6f2571b..ce7ce2ae27cd 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -285,11 +285,13 @@ kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
kexec_file_dbg_print = !!(flags & KEXEC_FILE_DEBUG);
image->file_mode = 1;

+#ifdef CONFIG_CRASH_DUMP
if (kexec_on_panic) {
/* Enable special crash kernel control page alloc policy. */
image->control_page = crashk_res.start;
image->type = KEXEC_TYPE_CRASH;
}
+#endif

ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
cmdline_ptr, cmdline_len, flags);
@@ -349,13 +351,14 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
if (!kexec_trylock())
return -EBUSY;

+#ifdef CONFIG_CRASH_DUMP
if (image_type == KEXEC_TYPE_CRASH) {
dest_image = &kexec_crash_image;
if (kexec_crash_image)
arch_kexec_unprotect_crashkres();
- } else {
+ } else
+#endif
dest_image = &kexec_image;
- }

if (flags & KEXEC_FILE_UNLOAD)
goto exchange;
@@ -419,8 +422,10 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
exchange:
image = xchg(dest_image, image);
out:
+#ifdef CONFIG_CRASH_DUMP
if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
arch_kexec_protect_crashkres();
+#endif

kexec_unlock();
kimage_free(image);
@@ -595,12 +600,14 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf,
static int kexec_walk_resources(struct kexec_buf *kbuf,
int (*func)(struct resource *, void *))
{
+#ifdef CONFIG_CRASH_DUMP
if (kbuf->image->type == KEXEC_TYPE_CRASH)
return walk_iomem_res_desc(crashk_res.desc,
IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
crashk_res.start, crashk_res.end,
kbuf, func);
- else if (kbuf->top_down)
+#endif
+ if (kbuf->top_down)
return walk_system_ram_res_rev(0, ULONG_MAX, kbuf, func);
else
return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 11526fc42bc2..fe7a517fc4ab 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -120,6 +120,7 @@ static ssize_t kexec_loaded_show(struct kobject *kobj,
}
KERNEL_ATTR_RO(kexec_loaded);

+#ifdef CONFIG_CRASH_DUMP
static ssize_t kexec_crash_loaded_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
@@ -152,6 +153,7 @@ static ssize_t kexec_crash_size_store(struct kobject *kobj,
}
KERNEL_ATTR_RW(kexec_crash_size);

+#endif /* CONFIG_CRASH_DUMP*/
#endif /* CONFIG_KEXEC_CORE */

#ifdef CONFIG_VMCORE_INFO
@@ -262,9 +264,11 @@ static struct attribute * kernel_attrs[] = {
#endif
#ifdef CONFIG_KEXEC_CORE
&kexec_loaded_attr.attr,
+#ifdef CONFIG_CRASH_DUMP
&kexec_crash_loaded_attr.attr,
&kexec_crash_size_attr.attr,
#endif
+#endif
#ifdef CONFIG_VMCORE_INFO
&vmcoreinfo_attr.attr,
#ifdef CONFIG_CRASH_HOTPLUG
--
2.41.0


2024-01-24 05:14:32

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 02/14] crash: split vmcoreinfo exporting code out from crash_core.c

Now move the relevant codes into separate files:
kernel/crash_reserve.c, include/linux/crash_reserve.h.

And add config item CRASH_RESERVE to control its enabling.

And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
<linux/crash_core.h> and config item dependency on CRASH_CORE
accordingly.

And also do renaming as follows:
- arch/xxx/kernel/{crash_core.c => vmcore_info.c}
because they are only related to vmcoreinfo exporting on x86, arm64,
riscv.

And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
decide if build in crash_core.c.

Signed-off-by: Baoquan He <[email protected]>
---
v2->v3:
- There's conflict when rebasing to linux-next in kernel/crash_core.c
because of below commits from Uladzislau:
commit 699d9351822e ("mm: vmalloc: Fix a warning in the crash_save_vmcoreinfo_init()")
commit 5f4c0c1e2a51 (:mm/vmalloc: remove vmap_area_list")

arch/arm64/kernel/Makefile | 2 +-
.../kernel/{crash_core.c => vmcore_info.c} | 2 +-
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/setup-common.c | 2 +-
arch/powerpc/platforms/powernv/opal-core.c | 2 +-
arch/riscv/kernel/Makefile | 2 +-
.../kernel/{crash_core.c => vmcore_info.c} | 2 +-
arch/x86/kernel/Makefile | 2 +-
.../{crash_core_32.c => vmcore_info_32.c} | 2 +-
.../{crash_core_64.c => vmcore_info_64.c} | 2 +-
drivers/firmware/qemu_fw_cfg.c | 14 +-
fs/proc/Kconfig | 2 +-
fs/proc/kcore.c | 2 +-
include/linux/buildid.h | 2 +-
include/linux/crash_core.h | 73 ------
include/linux/kexec.h | 1 +
include/linux/vmcore_info.h | 81 ++++++
kernel/Kconfig.kexec | 4 +-
kernel/Makefile | 4 +-
kernel/crash_core.c | 206 ----------------
kernel/ksysfs.c | 6 +-
kernel/printk/printk.c | 4 +-
kernel/vmcore_info.c | 231 ++++++++++++++++++
lib/buildid.c | 2 +-
24 files changed, 343 insertions(+), 309 deletions(-)
rename arch/arm64/kernel/{crash_core.c => vmcore_info.c} (97%)
rename arch/riscv/kernel/{crash_core.c => vmcore_info.c} (96%)
rename arch/x86/kernel/{crash_core_32.c => vmcore_info_32.c} (90%)
rename arch/x86/kernel/{crash_core_64.c => vmcore_info_64.c} (94%)
create mode 100644 include/linux/vmcore_info.h
create mode 100644 kernel/vmcore_info.c

diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index e5d03a7039b4..9fd638b91f38 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -66,7 +66,7 @@ obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_image.o
obj-$(CONFIG_ARM64_RELOC_TEST) += arm64-reloc-test.o
arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
-obj-$(CONFIG_CRASH_CORE) += crash_core.o
+obj-$(CONFIG_VMCORE_INFO) += vmcore_info.o
obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o
obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o
obj-$(CONFIG_ARM64_MTE) += mte.o
diff --git a/arch/arm64/kernel/crash_core.c b/arch/arm64/kernel/vmcore_info.c
similarity index 97%
rename from arch/arm64/kernel/crash_core.c
rename to arch/arm64/kernel/vmcore_info.c
index 2a24199a9b81..b19d5d6cb8b3 100644
--- a/arch/arm64/kernel/crash_core.c
+++ b/arch/arm64/kernel/vmcore_info.c
@@ -4,7 +4,7 @@
* Copyright (C) Huawei Futurewei Technologies.
*/

-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <asm/cpufeature.h>
#include <asm/memory.h>
#include <asm/pgtable-hwdef.h>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 7f704ae5c5ef..495d197c9b27 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -690,7 +690,7 @@ config ARCH_SELECTS_CRASH_DUMP
config FA_DUMP
bool "Firmware-assisted dump"
depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
- select CRASH_CORE
+ select VMCORE_INFO
select CRASH_RESERVE
select CRASH_DUMP
help
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 9b142b9d5187..733f210ffda1 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -109,7 +109,7 @@ int ppc_do_canonicalize_irqs;
EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
#endif

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
/* This keeps a track of which one is the crashing cpu. */
int crashing_cpu = -1;
#endif
diff --git a/arch/powerpc/platforms/powernv/opal-core.c b/arch/powerpc/platforms/powernv/opal-core.c
index bb7657115f1d..c9a9b759cc92 100644
--- a/arch/powerpc/platforms/powernv/opal-core.c
+++ b/arch/powerpc/platforms/powernv/opal-core.c
@@ -16,7 +16,7 @@
#include <linux/kobject.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/of.h>

#include <asm/page.h>
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index f71910718053..d6fd8dcfceb5 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -92,7 +92,7 @@ obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_KEXEC_CORE) += kexec_relocate.o crash_save_regs.o machine_kexec.o
obj-$(CONFIG_KEXEC_FILE) += elf_kexec.o machine_kexec_file.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
-obj-$(CONFIG_CRASH_CORE) += crash_core.o
+obj-$(CONFIG_VMCORE_INFO) += vmcore_info.o

obj-$(CONFIG_JUMP_LABEL) += jump_label.o

diff --git a/arch/riscv/kernel/crash_core.c b/arch/riscv/kernel/vmcore_info.c
similarity index 96%
rename from arch/riscv/kernel/crash_core.c
rename to arch/riscv/kernel/vmcore_info.c
index d18d529fd9b9..6d7a22522d63 100644
--- a/arch/riscv/kernel/crash_core.c
+++ b/arch/riscv/kernel/vmcore_info.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only

-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/pagemap.h>

void arch_crash_save_vmcoreinfo(void)
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0000325ab98f..913d4022131e 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -98,7 +98,7 @@ obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_X86_TSC) += trace_clock.o
obj-$(CONFIG_TRACING) += trace.o
obj-$(CONFIG_RETHOOK) += rethook.o
-obj-$(CONFIG_CRASH_CORE) += crash_core_$(BITS).o
+obj-$(CONFIG_VMCORE_INFO) += vmcore_info_$(BITS).o
obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
diff --git a/arch/x86/kernel/crash_core_32.c b/arch/x86/kernel/vmcore_info_32.c
similarity index 90%
rename from arch/x86/kernel/crash_core_32.c
rename to arch/x86/kernel/vmcore_info_32.c
index 8a89c109e20a..5995a749288a 100644
--- a/arch/x86/kernel/crash_core_32.c
+++ b/arch/x86/kernel/vmcore_info_32.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only

-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/pgtable.h>

#include <asm/setup.h>
diff --git a/arch/x86/kernel/crash_core_64.c b/arch/x86/kernel/vmcore_info_64.c
similarity index 94%
rename from arch/x86/kernel/crash_core_64.c
rename to arch/x86/kernel/vmcore_info_64.c
index 7d255f882afe..0dec7d868754 100644
--- a/arch/x86/kernel/crash_core_64.c
+++ b/arch/x86/kernel/vmcore_info_64.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only

-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/pgtable.h>

#include <asm/setup.h>
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c
index 03da9a4354f8..5f43dfa22f79 100644
--- a/drivers/firmware/qemu_fw_cfg.c
+++ b/drivers/firmware/qemu_fw_cfg.c
@@ -37,7 +37,7 @@
#include <uapi/linux/qemu_fw_cfg.h>
#include <linux/delay.h>
#include <linux/crash_dump.h>
-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>

MODULE_AUTHOR("Gabriel L. Somlo <[email protected]>");
MODULE_DESCRIPTION("QEMU fw_cfg sysfs support");
@@ -67,7 +67,7 @@ static void fw_cfg_sel_endianness(u16 key)
iowrite16(key, fw_cfg_reg_ctrl);
}

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
static inline bool fw_cfg_dma_enabled(void)
{
return (fw_cfg_rev & FW_CFG_VERSION_DMA) && fw_cfg_reg_dma;
@@ -156,7 +156,7 @@ static ssize_t fw_cfg_read_blob(u16 key,
return count;
}

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
/* write chunk of given fw_cfg blob (caller responsible for sanity-check) */
static ssize_t fw_cfg_write_blob(u16 key,
void *buf, loff_t pos, size_t count)
@@ -195,7 +195,7 @@ static ssize_t fw_cfg_write_blob(u16 key,

return ret;
}
-#endif /* CONFIG_CRASH_CORE */
+#endif /* CONFIG_VMCORE_INFO */

/* clean up fw_cfg device i/o */
static void fw_cfg_io_cleanup(void)
@@ -319,7 +319,7 @@ struct fw_cfg_sysfs_entry {
struct list_head list;
};

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
static ssize_t fw_cfg_write_vmcoreinfo(const struct fw_cfg_file *f)
{
static struct fw_cfg_vmcoreinfo *data;
@@ -343,7 +343,7 @@ static ssize_t fw_cfg_write_vmcoreinfo(const struct fw_cfg_file *f)
kfree(data);
return ret;
}
-#endif /* CONFIG_CRASH_CORE */
+#endif /* CONFIG_VMCORE_INFO */

/* get fw_cfg_sysfs_entry from kobject member */
static inline struct fw_cfg_sysfs_entry *to_entry(struct kobject *kobj)
@@ -583,7 +583,7 @@ static int fw_cfg_register_file(const struct fw_cfg_file *f)
int err;
struct fw_cfg_sysfs_entry *entry;

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
if (fw_cfg_dma_enabled() &&
strcmp(f->name, FW_CFG_VMCOREINFO_FILENAME) == 0 &&
!is_kdump_kernel()) {
diff --git a/fs/proc/Kconfig b/fs/proc/Kconfig
index 32b1116ae137..d80a1431ef7b 100644
--- a/fs/proc/Kconfig
+++ b/fs/proc/Kconfig
@@ -32,7 +32,7 @@ config PROC_FS
config PROC_KCORE
bool "/proc/kcore support" if !ARM
depends on PROC_FS && MMU
- select CRASH_CORE
+ select VMCORE_INFO
help
Provides a virtual ELF core file of the live kernel. This can
be read with gdb and other ELF tools. No modifications can be
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 6422e569b080..8e08a9a1b7ed 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -10,7 +10,7 @@
* Safe accesses to vmalloc/direct-mapped discontiguous areas, Kanoj Sarcar <[email protected]>
*/

-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/kcore.h>
diff --git a/include/linux/buildid.h b/include/linux/buildid.h
index 8a582d242f06..20aa3c2d89f7 100644
--- a/include/linux/buildid.h
+++ b/include/linux/buildid.h
@@ -11,7 +11,7 @@ int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id,
__u32 *size);
int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size);

-#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_CRASH_CORE)
+#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_VMCORE_INFO)
extern unsigned char vmlinux_build_id[BUILD_ID_SIZE_MAX];
void init_vmlinux_build_id(void);
#else
diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
index 1fde49246fa6..7f19f62018ef 100644
--- a/include/linux/crash_core.h
+++ b/include/linux/crash_core.h
@@ -6,79 +6,6 @@
#include <linux/elfcore.h>
#include <linux/elf.h>

-#define CRASH_CORE_NOTE_NAME "CORE"
-#define CRASH_CORE_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
-#define CRASH_CORE_NOTE_NAME_BYTES ALIGN(sizeof(CRASH_CORE_NOTE_NAME), 4)
-#define CRASH_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
-
-/*
- * The per-cpu notes area is a list of notes terminated by a "NULL"
- * note header. For kdump, the code in vmcore.c runs in the context
- * of the second kernel to combine them into one note.
- */
-#define CRASH_CORE_NOTE_BYTES ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
- CRASH_CORE_NOTE_NAME_BYTES + \
- CRASH_CORE_NOTE_DESC_BYTES)
-
-#define VMCOREINFO_BYTES PAGE_SIZE
-#define VMCOREINFO_NOTE_NAME "VMCOREINFO"
-#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
-#define VMCOREINFO_NOTE_SIZE ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
- VMCOREINFO_NOTE_NAME_BYTES + \
- VMCOREINFO_BYTES)
-
-typedef u32 note_buf_t[CRASH_CORE_NOTE_BYTES/4];
-/* Per cpu memory for storing cpu states in case of system crash. */
-extern note_buf_t __percpu *crash_notes;
-
-void crash_update_vmcoreinfo_safecopy(void *ptr);
-void crash_save_vmcoreinfo(void);
-void arch_crash_save_vmcoreinfo(void);
-__printf(1, 2)
-void vmcoreinfo_append_str(const char *fmt, ...);
-phys_addr_t paddr_vmcoreinfo_note(void);
-
-#define VMCOREINFO_OSRELEASE(value) \
- vmcoreinfo_append_str("OSRELEASE=%s\n", value)
-#define VMCOREINFO_BUILD_ID() \
- ({ \
- static_assert(sizeof(vmlinux_build_id) == 20); \
- vmcoreinfo_append_str("BUILD-ID=%20phN\n", vmlinux_build_id); \
- })
-
-#define VMCOREINFO_PAGESIZE(value) \
- vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
-#define VMCOREINFO_SYMBOL(name) \
- vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
-#define VMCOREINFO_SYMBOL_ARRAY(name) \
- vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)name)
-#define VMCOREINFO_SIZE(name) \
- vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
- (unsigned long)sizeof(name))
-#define VMCOREINFO_STRUCT_SIZE(name) \
- vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
- (unsigned long)sizeof(struct name))
-#define VMCOREINFO_OFFSET(name, field) \
- vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
- (unsigned long)offsetof(struct name, field))
-#define VMCOREINFO_TYPE_OFFSET(name, field) \
- vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
- (unsigned long)offsetof(name, field))
-#define VMCOREINFO_LENGTH(name, value) \
- vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
-#define VMCOREINFO_NUMBER(name) \
- vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
-#define VMCOREINFO_CONFIG(name) \
- vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
-
-extern unsigned char *vmcoreinfo_data;
-extern size_t vmcoreinfo_size;
-extern u32 *vmcoreinfo_note;
-
-Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
- void *data, size_t data_len);
-void final_note(Elf_Word *buf);
-
/* Alignment required for elf header segment */
#define ELF_CORE_HEADER_ALIGN 4096

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 6d79bfb52e5b..9c7bb8b56ed6 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -16,6 +16,7 @@
#if !defined(__ASSEMBLY__)

#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/crash_reserve.h>
#include <asm/io.h>
#include <linux/range.h>
diff --git a/include/linux/vmcore_info.h b/include/linux/vmcore_info.h
new file mode 100644
index 000000000000..e1dec1a6a749
--- /dev/null
+++ b/include/linux/vmcore_info.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_VMCORE_INFO_H
+#define LINUX_VMCORE_INFO_H
+
+#include <linux/linkage.h>
+#include <linux/elfcore.h>
+#include <linux/elf.h>
+
+#define CRASH_CORE_NOTE_NAME "CORE"
+#define CRASH_CORE_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
+#define CRASH_CORE_NOTE_NAME_BYTES ALIGN(sizeof(CRASH_CORE_NOTE_NAME), 4)
+#define CRASH_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
+
+/*
+ * The per-cpu notes area is a list of notes terminated by a "NULL"
+ * note header. For kdump, the code in vmcore.c runs in the context
+ * of the second kernel to combine them into one note.
+ */
+#define CRASH_CORE_NOTE_BYTES ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
+ CRASH_CORE_NOTE_NAME_BYTES + \
+ CRASH_CORE_NOTE_DESC_BYTES)
+
+#define VMCOREINFO_BYTES PAGE_SIZE
+#define VMCOREINFO_NOTE_NAME "VMCOREINFO"
+#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
+#define VMCOREINFO_NOTE_SIZE ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
+ VMCOREINFO_NOTE_NAME_BYTES + \
+ VMCOREINFO_BYTES)
+
+typedef u32 note_buf_t[CRASH_CORE_NOTE_BYTES/4];
+/* Per cpu memory for storing cpu states in case of system crash. */
+extern note_buf_t __percpu *crash_notes;
+
+void crash_update_vmcoreinfo_safecopy(void *ptr);
+void crash_save_vmcoreinfo(void);
+void arch_crash_save_vmcoreinfo(void);
+__printf(1, 2)
+void vmcoreinfo_append_str(const char *fmt, ...);
+phys_addr_t paddr_vmcoreinfo_note(void);
+
+#define VMCOREINFO_OSRELEASE(value) \
+ vmcoreinfo_append_str("OSRELEASE=%s\n", value)
+#define VMCOREINFO_BUILD_ID() \
+ ({ \
+ static_assert(sizeof(vmlinux_build_id) == 20); \
+ vmcoreinfo_append_str("BUILD-ID=%20phN\n", vmlinux_build_id); \
+ })
+
+#define VMCOREINFO_PAGESIZE(value) \
+ vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
+#define VMCOREINFO_SYMBOL(name) \
+ vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
+#define VMCOREINFO_SYMBOL_ARRAY(name) \
+ vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)name)
+#define VMCOREINFO_SIZE(name) \
+ vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
+ (unsigned long)sizeof(name))
+#define VMCOREINFO_STRUCT_SIZE(name) \
+ vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
+ (unsigned long)sizeof(struct name))
+#define VMCOREINFO_OFFSET(name, field) \
+ vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
+ (unsigned long)offsetof(struct name, field))
+#define VMCOREINFO_TYPE_OFFSET(name, field) \
+ vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
+ (unsigned long)offsetof(name, field))
+#define VMCOREINFO_LENGTH(name, value) \
+ vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
+#define VMCOREINFO_NUMBER(name) \
+ vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
+#define VMCOREINFO_CONFIG(name) \
+ vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
+
+extern unsigned char *vmcoreinfo_data;
+extern size_t vmcoreinfo_size;
+extern u32 *vmcoreinfo_note;
+
+Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
+ void *data, size_t data_len);
+void final_note(Elf_Word *buf);
+#endif /* LINUX_VMCORE_INFO_H */
diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec
index 8b7be71edd85..8faf27043432 100644
--- a/kernel/Kconfig.kexec
+++ b/kernel/Kconfig.kexec
@@ -5,11 +5,11 @@ menu "Kexec and crash features"
config CRASH_RESERVE
bool

-config CRASH_CORE
+config VMCORE_INFO
bool

config KEXEC_CORE
- select CRASH_CORE
+ select VMCORE_INFO
select CRASH_RESERVE
bool

diff --git a/kernel/Makefile b/kernel/Makefile
index 05fa88b3ab74..649272a1d6b9 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -68,9 +68,9 @@ obj-$(CONFIG_MODULE_SIG_FORMAT) += module_signature.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_KALLSYMS_SELFTEST) += kallsyms_selftest.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
-obj-$(CONFIG_CRASH_CORE) += crash_core.o
+obj-$(CONFIG_VMCORE_INFO) += vmcore_info.o
obj-$(CONFIG_CRASH_RESERVE) += crash_reserve.o
-obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
+obj-$(CONFIG_KEXEC_CORE) += kexec_core.o crash_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_KEXEC_ELF) += kexec_elf.o
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index ae0d1ce89b46..2f4df1fe6f7a 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -26,14 +26,6 @@
/* Per cpu memory for storing cpu states in case of system crash. */
note_buf_t __percpu *crash_notes;

-/* vmcoreinfo stuff */
-unsigned char *vmcoreinfo_data;
-size_t vmcoreinfo_size;
-u32 *vmcoreinfo_note;
-
-/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
-static unsigned char *vmcoreinfo_data_safecopy;
-
int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
void **addr, unsigned long *sz)
{
@@ -195,204 +187,6 @@ int crash_exclude_mem_range(struct crash_mem *mem,
return 0;
}

-Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
- void *data, size_t data_len)
-{
- struct elf_note *note = (struct elf_note *)buf;
-
- note->n_namesz = strlen(name) + 1;
- note->n_descsz = data_len;
- note->n_type = type;
- buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word));
- memcpy(buf, name, note->n_namesz);
- buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word));
- memcpy(buf, data, data_len);
- buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word));
-
- return buf;
-}
-
-void final_note(Elf_Word *buf)
-{
- memset(buf, 0, sizeof(struct elf_note));
-}
-
-static void update_vmcoreinfo_note(void)
-{
- u32 *buf = vmcoreinfo_note;
-
- if (!vmcoreinfo_size)
- return;
- buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
- vmcoreinfo_size);
- final_note(buf);
-}
-
-void crash_update_vmcoreinfo_safecopy(void *ptr)
-{
- if (ptr)
- memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size);
-
- vmcoreinfo_data_safecopy = ptr;
-}
-
-void crash_save_vmcoreinfo(void)
-{
- if (!vmcoreinfo_note)
- return;
-
- /* Use the safe copy to generate vmcoreinfo note if have */
- if (vmcoreinfo_data_safecopy)
- vmcoreinfo_data = vmcoreinfo_data_safecopy;
-
- vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
- update_vmcoreinfo_note();
-}
-
-void vmcoreinfo_append_str(const char *fmt, ...)
-{
- va_list args;
- char buf[0x50];
- size_t r;
-
- va_start(args, fmt);
- r = vscnprintf(buf, sizeof(buf), fmt, args);
- va_end(args);
-
- r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
-
- memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
-
- vmcoreinfo_size += r;
-
- WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES,
- "vmcoreinfo data exceeds allocated size, truncating");
-}
-
-/*
- * provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak arch_crash_save_vmcoreinfo(void)
-{}
-
-phys_addr_t __weak paddr_vmcoreinfo_note(void)
-{
- return __pa(vmcoreinfo_note);
-}
-EXPORT_SYMBOL(paddr_vmcoreinfo_note);
-
-static int __init crash_save_vmcoreinfo_init(void)
-{
- vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL);
- if (!vmcoreinfo_data) {
- pr_warn("Memory allocation for vmcoreinfo_data failed\n");
- return -ENOMEM;
- }
-
- vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE,
- GFP_KERNEL | __GFP_ZERO);
- if (!vmcoreinfo_note) {
- free_page((unsigned long)vmcoreinfo_data);
- vmcoreinfo_data = NULL;
- pr_warn("Memory allocation for vmcoreinfo_note failed\n");
- return -ENOMEM;
- }
-
- VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
- VMCOREINFO_BUILD_ID();
- VMCOREINFO_PAGESIZE(PAGE_SIZE);
-
- VMCOREINFO_SYMBOL(init_uts_ns);
- VMCOREINFO_OFFSET(uts_namespace, name);
- VMCOREINFO_SYMBOL(node_online_map);
-#ifdef CONFIG_MMU
- VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
-#endif
- VMCOREINFO_SYMBOL(_stext);
- vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", (unsigned long) VMALLOC_START);
-
-#ifndef CONFIG_NUMA
- VMCOREINFO_SYMBOL(mem_map);
- VMCOREINFO_SYMBOL(contig_page_data);
-#endif
-#ifdef CONFIG_SPARSEMEM
- VMCOREINFO_SYMBOL_ARRAY(mem_section);
- VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
- VMCOREINFO_STRUCT_SIZE(mem_section);
- VMCOREINFO_OFFSET(mem_section, section_mem_map);
- VMCOREINFO_NUMBER(SECTION_SIZE_BITS);
- VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS);
-#endif
- VMCOREINFO_STRUCT_SIZE(page);
- VMCOREINFO_STRUCT_SIZE(pglist_data);
- VMCOREINFO_STRUCT_SIZE(zone);
- VMCOREINFO_STRUCT_SIZE(free_area);
- VMCOREINFO_STRUCT_SIZE(list_head);
- VMCOREINFO_SIZE(nodemask_t);
- VMCOREINFO_OFFSET(page, flags);
- VMCOREINFO_OFFSET(page, _refcount);
- VMCOREINFO_OFFSET(page, mapping);
- VMCOREINFO_OFFSET(page, lru);
- VMCOREINFO_OFFSET(page, _mapcount);
- VMCOREINFO_OFFSET(page, private);
- VMCOREINFO_OFFSET(page, compound_head);
- VMCOREINFO_OFFSET(pglist_data, node_zones);
- VMCOREINFO_OFFSET(pglist_data, nr_zones);
-#ifdef CONFIG_FLATMEM
- VMCOREINFO_OFFSET(pglist_data, node_mem_map);
-#endif
- VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
- VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
- VMCOREINFO_OFFSET(pglist_data, node_id);
- VMCOREINFO_OFFSET(zone, free_area);
- VMCOREINFO_OFFSET(zone, vm_stat);
- VMCOREINFO_OFFSET(zone, spanned_pages);
- VMCOREINFO_OFFSET(free_area, free_list);
- VMCOREINFO_OFFSET(list_head, next);
- VMCOREINFO_OFFSET(list_head, prev);
- VMCOREINFO_LENGTH(zone.free_area, NR_PAGE_ORDERS);
- log_buf_vmcoreinfo_setup();
- VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
- VMCOREINFO_NUMBER(NR_FREE_PAGES);
- VMCOREINFO_NUMBER(PG_lru);
- VMCOREINFO_NUMBER(PG_private);
- VMCOREINFO_NUMBER(PG_swapcache);
- VMCOREINFO_NUMBER(PG_swapbacked);
- VMCOREINFO_NUMBER(PG_slab);
-#ifdef CONFIG_MEMORY_FAILURE
- VMCOREINFO_NUMBER(PG_hwpoison);
-#endif
- VMCOREINFO_NUMBER(PG_head_mask);
-#define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy)
- VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
-#ifdef CONFIG_HUGETLB_PAGE
- VMCOREINFO_NUMBER(PG_hugetlb);
-#define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline)
- VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);
-#endif
-
-#ifdef CONFIG_KALLSYMS
- VMCOREINFO_SYMBOL(kallsyms_names);
- VMCOREINFO_SYMBOL(kallsyms_num_syms);
- VMCOREINFO_SYMBOL(kallsyms_token_table);
- VMCOREINFO_SYMBOL(kallsyms_token_index);
-#ifdef CONFIG_KALLSYMS_BASE_RELATIVE
- VMCOREINFO_SYMBOL(kallsyms_offsets);
- VMCOREINFO_SYMBOL(kallsyms_relative_base);
-#else
- VMCOREINFO_SYMBOL(kallsyms_addresses);
-#endif /* CONFIG_KALLSYMS_BASE_RELATIVE */
-#endif /* CONFIG_KALLSYMS */
-
- arch_crash_save_vmcoreinfo();
- update_vmcoreinfo_note();
-
- return 0;
-}
-
-subsys_initcall(crash_save_vmcoreinfo_init);
-
static int __init crash_notes_memory_init(void)
{
/* Allocate memory for saving cpu registers. */
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 1d4bc493b2f4..11526fc42bc2 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -154,7 +154,7 @@ KERNEL_ATTR_RW(kexec_crash_size);

#endif /* CONFIG_KEXEC_CORE */

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO

static ssize_t vmcoreinfo_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
@@ -177,7 +177,7 @@ KERNEL_ATTR_RO(crash_elfcorehdr_size);

#endif

-#endif /* CONFIG_CRASH_CORE */
+#endif /* CONFIG_VMCORE_INFO */

/* whether file capabilities are enabled */
static ssize_t fscaps_show(struct kobject *kobj,
@@ -265,7 +265,7 @@ static struct attribute * kernel_attrs[] = {
&kexec_crash_loaded_attr.attr,
&kexec_crash_size_attr.attr,
#endif
-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
&vmcoreinfo_attr.attr,
#ifdef CONFIG_CRASH_HOTPLUG
&crash_elfcorehdr_size_attr.attr,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index f2444b581e16..7d74b000b43a 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -34,7 +34,7 @@
#include <linux/security.h>
#include <linux/memblock.h>
#include <linux/syscalls.h>
-#include <linux/crash_core.h>
+#include <linux/vmcore_info.h>
#include <linux/ratelimit.h>
#include <linux/kmsg_dump.h>
#include <linux/syslog.h>
@@ -951,7 +951,7 @@ const struct file_operations kmsg_fops = {
.release = devkmsg_release,
};

-#ifdef CONFIG_CRASH_CORE
+#ifdef CONFIG_VMCORE_INFO
/*
* This appends the listed symbols to /proc/vmcore
*
diff --git a/kernel/vmcore_info.c b/kernel/vmcore_info.c
new file mode 100644
index 000000000000..8f48c0a42e2e
--- /dev/null
+++ b/kernel/vmcore_info.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * crash.c - kernel crash support code.
+ * Copyright (C) 2002-2004 Eric Biederman <[email protected]>
+ */
+
+#include <linux/buildid.h>
+#include <linux/init.h>
+#include <linux/utsname.h>
+#include <linux/vmalloc.h>
+#include <linux/sizes.h>
+#include <linux/kexec.h>
+#include <linux/memory.h>
+#include <linux/cpuhotplug.h>
+#include <linux/memblock.h>
+#include <linux/kexec.h>
+#include <linux/kmemleak.h>
+
+#include <asm/page.h>
+#include <asm/sections.h>
+
+#include <crypto/sha1.h>
+
+#include "kallsyms_internal.h"
+#include "kexec_internal.h"
+
+/* vmcoreinfo stuff */
+unsigned char *vmcoreinfo_data;
+size_t vmcoreinfo_size;
+u32 *vmcoreinfo_note;
+
+/* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */
+static unsigned char *vmcoreinfo_data_safecopy;
+
+Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
+ void *data, size_t data_len)
+{
+ struct elf_note *note = (struct elf_note *)buf;
+
+ note->n_namesz = strlen(name) + 1;
+ note->n_descsz = data_len;
+ note->n_type = type;
+ buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word));
+ memcpy(buf, name, note->n_namesz);
+ buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word));
+ memcpy(buf, data, data_len);
+ buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word));
+
+ return buf;
+}
+
+void final_note(Elf_Word *buf)
+{
+ memset(buf, 0, sizeof(struct elf_note));
+}
+
+static void update_vmcoreinfo_note(void)
+{
+ u32 *buf = vmcoreinfo_note;
+
+ if (!vmcoreinfo_size)
+ return;
+ buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
+ vmcoreinfo_size);
+ final_note(buf);
+}
+
+void crash_update_vmcoreinfo_safecopy(void *ptr)
+{
+ if (ptr)
+ memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size);
+
+ vmcoreinfo_data_safecopy = ptr;
+}
+
+void crash_save_vmcoreinfo(void)
+{
+ if (!vmcoreinfo_note)
+ return;
+
+ /* Use the safe copy to generate vmcoreinfo note if have */
+ if (vmcoreinfo_data_safecopy)
+ vmcoreinfo_data = vmcoreinfo_data_safecopy;
+
+ vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds());
+ update_vmcoreinfo_note();
+}
+
+void vmcoreinfo_append_str(const char *fmt, ...)
+{
+ va_list args;
+ char buf[0x50];
+ size_t r;
+
+ va_start(args, fmt);
+ r = vscnprintf(buf, sizeof(buf), fmt, args);
+ va_end(args);
+
+ r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size);
+
+ memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
+
+ vmcoreinfo_size += r;
+
+ WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES,
+ "vmcoreinfo data exceeds allocated size, truncating");
+}
+
+/*
+ * provide an empty default implementation here -- architecture
+ * code may override this
+ */
+void __weak arch_crash_save_vmcoreinfo(void)
+{}
+
+phys_addr_t __weak paddr_vmcoreinfo_note(void)
+{
+ return __pa(vmcoreinfo_note);
+}
+EXPORT_SYMBOL(paddr_vmcoreinfo_note);
+
+static int __init crash_save_vmcoreinfo_init(void)
+{
+ vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL);
+ if (!vmcoreinfo_data) {
+ pr_warn("Memory allocation for vmcoreinfo_data failed\n");
+ return -ENOMEM;
+ }
+
+ vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE,
+ GFP_KERNEL | __GFP_ZERO);
+ if (!vmcoreinfo_note) {
+ free_page((unsigned long)vmcoreinfo_data);
+ vmcoreinfo_data = NULL;
+ pr_warn("Memory allocation for vmcoreinfo_note failed\n");
+ return -ENOMEM;
+ }
+
+ VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
+ VMCOREINFO_BUILD_ID();
+ VMCOREINFO_PAGESIZE(PAGE_SIZE);
+
+ VMCOREINFO_SYMBOL(init_uts_ns);
+ VMCOREINFO_OFFSET(uts_namespace, name);
+ VMCOREINFO_SYMBOL(node_online_map);
+#ifdef CONFIG_MMU
+ VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
+#endif
+ VMCOREINFO_SYMBOL(_stext);
+ vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", (unsigned long) VMALLOC_START);
+
+#ifndef CONFIG_NUMA
+ VMCOREINFO_SYMBOL(mem_map);
+ VMCOREINFO_SYMBOL(contig_page_data);
+#endif
+#ifdef CONFIG_SPARSEMEM
+ VMCOREINFO_SYMBOL_ARRAY(mem_section);
+ VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
+ VMCOREINFO_STRUCT_SIZE(mem_section);
+ VMCOREINFO_OFFSET(mem_section, section_mem_map);
+ VMCOREINFO_NUMBER(SECTION_SIZE_BITS);
+ VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS);
+#endif
+ VMCOREINFO_STRUCT_SIZE(page);
+ VMCOREINFO_STRUCT_SIZE(pglist_data);
+ VMCOREINFO_STRUCT_SIZE(zone);
+ VMCOREINFO_STRUCT_SIZE(free_area);
+ VMCOREINFO_STRUCT_SIZE(list_head);
+ VMCOREINFO_SIZE(nodemask_t);
+ VMCOREINFO_OFFSET(page, flags);
+ VMCOREINFO_OFFSET(page, _refcount);
+ VMCOREINFO_OFFSET(page, mapping);
+ VMCOREINFO_OFFSET(page, lru);
+ VMCOREINFO_OFFSET(page, _mapcount);
+ VMCOREINFO_OFFSET(page, private);
+ VMCOREINFO_OFFSET(page, compound_head);
+ VMCOREINFO_OFFSET(pglist_data, node_zones);
+ VMCOREINFO_OFFSET(pglist_data, nr_zones);
+#ifdef CONFIG_FLATMEM
+ VMCOREINFO_OFFSET(pglist_data, node_mem_map);
+#endif
+ VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
+ VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
+ VMCOREINFO_OFFSET(pglist_data, node_id);
+ VMCOREINFO_OFFSET(zone, free_area);
+ VMCOREINFO_OFFSET(zone, vm_stat);
+ VMCOREINFO_OFFSET(zone, spanned_pages);
+ VMCOREINFO_OFFSET(free_area, free_list);
+ VMCOREINFO_OFFSET(list_head, next);
+ VMCOREINFO_OFFSET(list_head, prev);
+ VMCOREINFO_LENGTH(zone.free_area, NR_PAGE_ORDERS);
+ log_buf_vmcoreinfo_setup();
+ VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
+ VMCOREINFO_NUMBER(NR_FREE_PAGES);
+ VMCOREINFO_NUMBER(PG_lru);
+ VMCOREINFO_NUMBER(PG_private);
+ VMCOREINFO_NUMBER(PG_swapcache);
+ VMCOREINFO_NUMBER(PG_swapbacked);
+ VMCOREINFO_NUMBER(PG_slab);
+#ifdef CONFIG_MEMORY_FAILURE
+ VMCOREINFO_NUMBER(PG_hwpoison);
+#endif
+ VMCOREINFO_NUMBER(PG_head_mask);
+#define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy)
+ VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+#ifdef CONFIG_HUGETLB_PAGE
+ VMCOREINFO_NUMBER(PG_hugetlb);
+#define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline)
+ VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE);
+#endif
+
+#ifdef CONFIG_KALLSYMS
+ VMCOREINFO_SYMBOL(kallsyms_names);
+ VMCOREINFO_SYMBOL(kallsyms_num_syms);
+ VMCOREINFO_SYMBOL(kallsyms_token_table);
+ VMCOREINFO_SYMBOL(kallsyms_token_index);
+#ifdef CONFIG_KALLSYMS_BASE_RELATIVE
+ VMCOREINFO_SYMBOL(kallsyms_offsets);
+ VMCOREINFO_SYMBOL(kallsyms_relative_base);
+#else
+ VMCOREINFO_SYMBOL(kallsyms_addresses);
+#endif /* CONFIG_KALLSYMS_BASE_RELATIVE */
+#endif /* CONFIG_KALLSYMS */
+
+ arch_crash_save_vmcoreinfo();
+ update_vmcoreinfo_note();
+
+ return 0;
+}
+
+subsys_initcall(crash_save_vmcoreinfo_init);
diff --git a/lib/buildid.c b/lib/buildid.c
index e3a7acdeef0e..3e6868c86b45 100644
--- a/lib/buildid.c
+++ b/lib/buildid.c
@@ -174,7 +174,7 @@ int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size)
return parse_build_id_buf(build_id, NULL, buf, buf_size);
}

-#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_CRASH_CORE)
+#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_VMCORE_INFO)
unsigned char vmlinux_build_id[BUILD_ID_SIZE_MAX] __ro_after_init;

/**
--
2.41.0


2024-01-24 05:14:36

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 05/14] crash: clean up kdump related config items

By splitting CRASH_RESERVE and VMCORE_INFO out from CRASH_CORE, cleaning
up the dependency of FA_DMUMP on CRASH_DUMP, and moving crash codes from
kexec_core.c to crash_core.c, now we can rearrange CRASH_DUMP to
depend on KEXEC_CORE, and make CRASH_DUMP select CRASH_RESERVE and
VMCORE_INFO.

KEXEC_CORE won't select CRASH_RESERVE and VMCORE_INFO any more because
KEXEC_CORE enables codes which allocate control pages, copy
kexec/kdump segments, and prepare for switching. These codes are shared
by both kexec reboot and crash dumping.

Doing this makes codes and the corresponding config items more
logical (the right item depends on or is selected by the left item).

PROC_KCORE -----------> VMCORE_INFO

|----------> VMCORE_INFO
FA_DUMP----|
|----------> CRASH_RESERVE

---->VMCORE_INFO
/
|---->CRASH_RESERVE
KEXEC --| /|
|--> KEXEC_CORE--> CRASH_DUMP-->/-|---->PROC_VMCORE
KEXEC_FILE --| \ |
\---->CRASH_HOTPLUG

KEXEC --|
|--> KEXEC_CORE--> kexec reboot
KEXEC_FILE --|

Signed-off-by: Baoquan He <[email protected]>
---
kernel/Kconfig.kexec | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec
index 8faf27043432..6c34e63c88ff 100644
--- a/kernel/Kconfig.kexec
+++ b/kernel/Kconfig.kexec
@@ -9,8 +9,6 @@ config VMCORE_INFO
bool

config KEXEC_CORE
- select VMCORE_INFO
- select CRASH_RESERVE
bool

config KEXEC_ELF
@@ -99,8 +97,11 @@ config KEXEC_JUMP

config CRASH_DUMP
bool "kernel crash dumps"
+ default y
depends on ARCH_SUPPORTS_CRASH_DUMP
- select KEXEC_CORE
+ depends on KEXEC_CORE
+ select VMCORE_INFO
+ select CRASH_RESERVE
help
Generate crash dump after being started by kexec.
This should be normally only set in special crash dump kernels
--
2.41.0


2024-01-24 05:14:51

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on x86 with some adjustments.

Here, also change some ifdefs or IS_ENABLED() check to more appropriate
ones, e,g
- #ifdef CONFIG_KEXEC_CORE -> #ifdef CONFIG_CRASH_DUMP
- (!IS_ENABLED(CONFIG_KEXEC_CORE)) - > (!IS_ENABLED(CONFIG_CRASH_RESERVE))

Signed-off-by: Baoquan He <[email protected]>
---
arch/x86/kernel/Makefile | 4 ++--
arch/x86/kernel/cpu/mshyperv.c | 4 ++++
arch/x86/kernel/kexec-bzimage64.c | 4 ++++
arch/x86/kernel/kvm.c | 4 ++--
arch/x86/kernel/machine_kexec_64.c | 3 +++
arch/x86/kernel/reboot.c | 2 +-
arch/x86/kernel/setup.c | 2 +-
arch/x86/kernel/smp.c | 2 +-
arch/x86/xen/enlighten_hvm.c | 4 ++++
9 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 913d4022131e..3668b1edef2d 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -100,9 +100,9 @@ obj-$(CONFIG_TRACING) += trace.o
obj-$(CONFIG_RETHOOK) += rethook.o
obj-$(CONFIG_VMCORE_INFO) += vmcore_info_$(BITS).o
obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
-obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
+obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o
obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
-obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
+obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o crash.o
obj-y += kprobes/
obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_X86_32) += doublefault_32.o
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 01fa06dd06b6..f8163a59026b 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
hyperv_cleanup();
}

+#ifdef CONFIG_CRASH_DUMP
static void hv_machine_crash_shutdown(struct pt_regs *regs)
{
if (hv_crash_handler)
@@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
/* Disable the hypercall page when there is only 1 active CPU. */
hyperv_cleanup();
}
+#endif
#endif /* CONFIG_KEXEC_CORE */
#endif /* CONFIG_HYPERV */

@@ -497,7 +499,9 @@ static void __init ms_hyperv_init_platform(void)

#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
machine_ops.shutdown = hv_machine_shutdown;
+#ifdef CONFIG_CRASH_DUMP
machine_ops.crash_shutdown = hv_machine_crash_shutdown;
+#endif
#endif
if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
/*
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index 2a422e00ed4b..b55737b83a84 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -263,11 +263,13 @@ setup_boot_parameters(struct kimage *image, struct boot_params *params,
memset(&params->hd0_info, 0, sizeof(params->hd0_info));
memset(&params->hd1_info, 0, sizeof(params->hd1_info));

+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH) {
ret = crash_setup_memmap_entries(image, params);
if (ret)
return ret;
} else
+#endif
setup_e820_entries(params);

nr_e820_entries = params->e820_entries;
@@ -433,12 +435,14 @@ static void *bzImage64_load(struct kimage *image, char *kernel,
return ERR_PTR(-EINVAL);
}

+#ifdef CONFIG_CRASH_DUMP
/* Allocate and load backup region */
if (image->type == KEXEC_TYPE_CRASH) {
ret = crash_load_segments(image);
if (ret)
return ERR_PTR(ret);
}
+#endif

/*
* Load purgatory. For 64bit entry point, purgatory code can be
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index dfe9945b9bec..acfc2d3183bc 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -769,7 +769,7 @@ static struct notifier_block kvm_pv_reboot_nb = {
* won't be valid. In cases like kexec, in which you install a new kernel, this
* means a random memory location will be kept being written.
*/
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
static void kvm_crash_shutdown(struct pt_regs *regs)
{
kvm_guest_cpu_offline(true);
@@ -852,7 +852,7 @@ static void __init kvm_guest_init(void)
kvm_guest_cpu_init();
#endif

-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
machine_ops.crash_shutdown = kvm_crash_shutdown;
#endif

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index bc0a5348b4a6..b180d8e497c3 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -508,6 +508,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
}
#endif /* CONFIG_KEXEC_FILE */

+#ifdef CONFIG_CRASH_DUMP
+
static int
kexec_mark_range(unsigned long start, unsigned long end, bool protect)
{
@@ -552,6 +554,7 @@ void arch_kexec_unprotect_crashkres(void)
{
kexec_mark_crashkres(false);
}
+#endif

/*
* During a traditional boot under SME, SME will encrypt the kernel,
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 830425e6d38e..1287b0d5962f 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -796,7 +796,7 @@ struct machine_ops machine_ops __ro_after_init = {
.emergency_restart = native_machine_emergency_restart,
.restart = native_machine_restart,
.halt = native_machine_halt,
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
.crash_shutdown = native_machine_crash_shutdown,
#endif
};
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 84201071dfac..899d839a2954 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -471,7 +471,7 @@ static void __init arch_reserve_crashkernel(void)
bool high = false;
int ret;

- if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;

ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 2908e063d7d8..18266cc3d98c 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -286,7 +286,7 @@ struct smp_ops smp_ops = {
.smp_cpus_done = native_smp_cpus_done,

.stop_other_cpus = native_stop_other_cpus,
-#if defined(CONFIG_KEXEC_CORE)
+#if defined(CONFIG_CRASH_DUMP)
.crash_stop_other_cpus = kdump_nmi_shootdown_cpus,
#endif
.smp_send_reschedule = native_smp_send_reschedule,
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 3f8c34707c50..09e3db7ff990 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -149,12 +149,14 @@ static void xen_hvm_shutdown(void)
xen_reboot(SHUTDOWN_soft_reset);
}

+#ifdef CONFIG_CRASH_DUMP
static void xen_hvm_crash_shutdown(struct pt_regs *regs)
{
native_machine_crash_shutdown(regs);
xen_reboot(SHUTDOWN_soft_reset);
}
#endif
+#endif

static int xen_cpu_up_prepare_hvm(unsigned int cpu)
{
@@ -236,8 +238,10 @@ static void __init xen_hvm_guest_init(void)

#ifdef CONFIG_KEXEC_CORE
machine_ops.shutdown = xen_hvm_shutdown;
+#ifdef CONFIG_CRASH_DUMP
machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
#endif
+#endif
}

static __init int xen_parse_nopv(char *arg)
--
2.41.0


2024-01-24 05:15:25

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 07/14] arm64, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on arm64 with some adjustments.

Here wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery.

Signed-off-by: Baoquan He <[email protected]>
---
arch/arm64/include/asm/kexec.h | 2 +-
arch/arm64/kernel/machine_kexec.c | 2 +-
arch/arm64/kernel/machine_kexec_file.c | 10 ++++++++--
arch/arm64/mm/init.c | 2 +-
4 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
index 9ac9572a3bbe..4d9cc7a76d9c 100644
--- a/arch/arm64/include/asm/kexec.h
+++ b/arch/arm64/include/asm/kexec.h
@@ -80,7 +80,7 @@ static inline void crash_setup_regs(struct pt_regs *newregs,
}
}

-#if defined(CONFIG_KEXEC_CORE) && defined(CONFIG_HIBERNATION)
+#if defined(CONFIG_CRASH_DUMP) && defined(CONFIG_HIBERNATION)
extern bool crash_is_nosave(unsigned long pfn);
extern void crash_prepare_suspend(void);
extern void crash_post_resume(void);
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index b38aae5b488d..82e2203d86a3 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -255,7 +255,7 @@ void machine_crash_shutdown(struct pt_regs *regs)
pr_info("Starting crashdump kernel...\n");
}

-#ifdef CONFIG_HIBERNATION
+#if defined(CONFIG_CRASH_DUMP) && defined(CONFIG_HIBERNATION)
/*
* To preserve the crash dump kernel image, the relevant memory segments
* should be mapped again around the hibernation.
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 0e017358f4ba..af1ca875c52c 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -39,6 +39,7 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
return kexec_image_post_load_cleanup_default(image);
}

+#ifdef CONFIG_CRASH_DUMP
static int prepare_elf_headers(void **addr, unsigned long *sz)
{
struct crash_mem *cmem;
@@ -80,6 +81,7 @@ static int prepare_elf_headers(void **addr, unsigned long *sz)
kfree(cmem);
return ret;
}
+#endif

/*
* Tries to add the initrd and DTB to the image. If it is not possible to find
@@ -93,8 +95,8 @@ int load_other_segments(struct kimage *image,
char *cmdline)
{
struct kexec_buf kbuf;
- void *headers, *dtb = NULL;
- unsigned long headers_sz, initrd_load_addr = 0, dtb_len,
+ void *dtb = NULL;
+ unsigned long initrd_load_addr = 0, dtb_len,
orig_segments = image->nr_segments;
int ret = 0;

@@ -102,7 +104,10 @@ int load_other_segments(struct kimage *image,
/* not allocate anything below the kernel */
kbuf.buf_min = kernel_load_addr + kernel_size;

+#ifdef CONFIG_CRASH_DUMP
/* load elf core header */
+ void *headers;
+ unsigned long headers_sz;
if (image->type == KEXEC_TYPE_CRASH) {
ret = prepare_elf_headers(&headers, &headers_sz);
if (ret) {
@@ -130,6 +135,7 @@ int load_other_segments(struct kimage *image,
kexec_dprintk("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
image->elf_load_addr, kbuf.bufsz, kbuf.memsz);
}
+#endif

/* load initrd */
if (initrd) {
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 74c1db8ce271..c1f6213e77f3 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -100,7 +100,7 @@ static void __init arch_reserve_crashkernel(void)
bool high = false;
int ret;

- if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;

ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
--
2.41.0


2024-01-24 05:15:38

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 08/14] ppc, crash: enforce KEXEC and KEXEC_FILE to select CRASH_DUMP

In PowerPC, the crash dumping and kexec reboot share code in
arch_kexec_locate_mem_hole(), in which struct crash_mem is used.

Here enfoce enforce KEXEC and KEXEC_FILE to select CRASH_DUMP for now.

Signed-off-by: Baoquan He <[email protected]>
---
arch/powerpc/Kconfig | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e66fd9923250..31f013e636e3 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -608,6 +608,10 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
config ARCH_SUPPORTS_KEXEC
def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP)

+config ARCH_SELECTS_KEXEC
+ def_bool y
+ select CRASH_DUMP
+
config ARCH_SUPPORTS_KEXEC_FILE
def_bool PPC64

@@ -618,6 +622,7 @@ config ARCH_SELECTS_KEXEC_FILE
def_bool y
depends on KEXEC_FILE
select KEXEC_ELF
+ select CRASH_DUMP
select HAVE_IMA_KEXEC if IMA

config PPC64_BIG_ENDIAN_ELF_ABI_V2
--
2.41.0


2024-01-24 05:15:53

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 09/14] s390, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on s390 with some adjustments.

Here wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery.

Signed-off-by: Baoquan He <[email protected]>
---
arch/s390/kernel/kexec_elf.c | 2 ++
arch/s390/kernel/kexec_image.c | 2 ++
arch/s390/kernel/machine_kexec_file.c | 10 ++++++++++
3 files changed, 14 insertions(+)

diff --git a/arch/s390/kernel/kexec_elf.c b/arch/s390/kernel/kexec_elf.c
index 9da6fa30c447..4d364de43799 100644
--- a/arch/s390/kernel/kexec_elf.c
+++ b/arch/s390/kernel/kexec_elf.c
@@ -40,8 +40,10 @@ static int kexec_file_add_kernel_elf(struct kimage *image,
buf.bufsz = phdr->p_filesz;

buf.mem = ALIGN(phdr->p_paddr, phdr->p_align);
+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
+#endif
buf.memsz = phdr->p_memsz;
data->memsz = ALIGN(data->memsz, phdr->p_align) + buf.memsz;

diff --git a/arch/s390/kernel/kexec_image.c b/arch/s390/kernel/kexec_image.c
index af23eff5774d..a32ce8bea745 100644
--- a/arch/s390/kernel/kexec_image.c
+++ b/arch/s390/kernel/kexec_image.c
@@ -24,8 +24,10 @@ static int kexec_file_add_kernel_image(struct kimage *image,
buf.bufsz = image->kernel_buf_len;

buf.mem = 0;
+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
+#endif
buf.memsz = buf.bufsz;

data->kernel_buf = image->kernel_buf;
diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c
index 8d207b82d9fe..c2bac14dd668 100644
--- a/arch/s390/kernel/machine_kexec_file.c
+++ b/arch/s390/kernel/machine_kexec_file.c
@@ -105,6 +105,7 @@ static int kexec_file_update_purgatory(struct kimage *image,
if (ret)
return ret;

+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH) {
u64 crash_size;

@@ -121,6 +122,7 @@ static int kexec_file_update_purgatory(struct kimage *image,
sizeof(crash_size),
false);
}
+#endif
return ret;
}

@@ -134,8 +136,10 @@ static int kexec_file_add_purgatory(struct kimage *image,

data->memsz = ALIGN(data->memsz, PAGE_SIZE);
buf.mem = data->memsz;
+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
+#endif

ret = kexec_load_purgatory(image, &buf);
if (ret)
@@ -158,8 +162,10 @@ static int kexec_file_add_initrd(struct kimage *image,

data->memsz = ALIGN(data->memsz, PAGE_SIZE);
buf.mem = data->memsz;
+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
+#endif
buf.memsz = buf.bufsz;

data->parm->initrd_start = data->memsz;
@@ -223,8 +229,10 @@ static int kexec_file_add_ipl_report(struct kimage *image,
data->kernel_buf + offsetof(struct lowcore, ipl_parmblock_ptr);
*lc_ipl_parmblock_ptr = (__u32)buf.mem;

+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
+#endif

ret = kexec_add_buffer(&buf);
out:
@@ -268,10 +276,12 @@ void *kexec_file_add_components(struct kimage *image,
memcpy(data.parm->command_line, image->cmdline_buf,
image->cmdline_buf_len);

+#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH) {
data.parm->oldmem_base = crashk_res.start;
data.parm->oldmem_size = crashk_res.end - crashk_res.start + 1;
}
+#endif

if (image->initrd_buf) {
ret = kexec_file_add_initrd(image, &data);
--
2.41.0


2024-01-24 05:16:26

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 11/14] mips, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on mips with some adjustments.

Here use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
in the crashkernel reservation code.

Signed-off-by: Baoquan He <[email protected]>
---
arch/mips/kernel/setup.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 9c30de151597..12a1a4ffb602 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -442,8 +442,6 @@ static void __init mips_reserve_vmcore(void)
#endif
}

-#ifdef CONFIG_KEXEC
-
/* 64M alignment for crash kernel regions */
#define CRASH_ALIGN SZ_64M
#define CRASH_ADDR_MAX SZ_512M
@@ -454,6 +452,9 @@ static void __init mips_parse_crashkernel(void)
unsigned long long crash_size, crash_base;
int ret;

+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
+ return;
+
total_mem = memblock_phys_mem_size();
ret = parse_crashkernel(boot_command_line, total_mem,
&crash_size, &crash_base,
@@ -489,6 +490,9 @@ static void __init request_crashkernel(struct resource *res)
{
int ret;

+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
+ return;
+
if (crashk_res.start == crashk_res.end)
return;

@@ -498,15 +502,6 @@ static void __init request_crashkernel(struct resource *res)
(unsigned long)(resource_size(&crashk_res) >> 20),
(unsigned long)(crashk_res.start >> 20));
}
-#else /* !defined(CONFIG_KEXEC) */
-static void __init mips_parse_crashkernel(void)
-{
-}
-
-static void __init request_crashkernel(struct resource *res)
-{
-}
-#endif /* !defined(CONFIG_KEXEC) */

static void __init check_kernel_sections_mem(void)
{
--
2.41.0


2024-01-24 05:16:37

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 10/14] sh, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on SuperH with some adjustments.

wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery, and
use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
in the crashkernel reservation code.

Signed-off-by: Baoquan He <[email protected]>
---
arch/sh/kernel/machine_kexec.c | 3 +++
arch/sh/kernel/setup.c | 2 +-
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index fa3a7b36190a..8daa8a6e6fa6 100644
--- a/arch/sh/kernel/machine_kexec.c
+++ b/arch/sh/kernel/machine_kexec.c
@@ -153,6 +153,9 @@ void __init reserve_crashkernel(void)
unsigned long long crash_size, crash_base;
int ret;

+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
+ return;
+
ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
&crash_size, &crash_base, NULL, NULL);
if (ret == 0 && crash_size > 0) {
diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index d3175f09b3aa..620e5cf8ae1e 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -220,7 +220,7 @@ void __init __add_active_range(unsigned int nid, unsigned long start_pfn,
request_resource(res, &code_resource);
request_resource(res, &data_resource);
request_resource(res, &bss_resource);
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_RESERVE
request_resource(res, &crashk_res);
#endif

--
2.41.0


2024-01-24 05:16:52

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 12/14] riscv, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on risc-v with some adjustments.

Here wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery, and
use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
in the crashkernel reservation code.

Signed-off-by: Baoquan He <[email protected]>
---
arch/riscv/kernel/elf_kexec.c | 9 +++++++--
arch/riscv/mm/init.c | 2 +-
2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/kernel/elf_kexec.c b/arch/riscv/kernel/elf_kexec.c
index 5bd1ec3341fe..54260c16f991 100644
--- a/arch/riscv/kernel/elf_kexec.c
+++ b/arch/riscv/kernel/elf_kexec.c
@@ -117,6 +117,7 @@ static int elf_find_pbase(struct kimage *image, unsigned long kernel_len,
return ret;
}

+#ifdef CONFIG_CRASH_DUMP
static int get_nr_ram_ranges_callback(struct resource *res, void *arg)
{
unsigned int *nr_ranges = arg;
@@ -189,6 +190,7 @@ static char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
cmdline_ptr[COMMAND_LINE_SIZE - 1] = '\0';
return cmdline_ptr;
}
+#endif

static void *elf_kexec_load(struct kimage *image, char *kernel_buf,
unsigned long kernel_len, char *initrd,
@@ -196,12 +198,11 @@ static void *elf_kexec_load(struct kimage *image, char *kernel_buf,
unsigned long cmdline_len)
{
int ret;
+ void *fdt;
unsigned long old_kernel_pbase = ULONG_MAX;
unsigned long new_kernel_pbase = 0UL;
unsigned long initrd_pbase = 0UL;
- unsigned long headers_sz;
unsigned long kernel_start;
- void *fdt, *headers;
struct elfhdr ehdr;
struct kexec_buf kbuf;
struct kexec_elf_info elf_info;
@@ -227,8 +228,11 @@ static void *elf_kexec_load(struct kimage *image, char *kernel_buf,
kbuf.buf_min = new_kernel_pbase + kernel_len;
kbuf.buf_max = ULONG_MAX;

+#ifdef CONFIG_CRASH_DUMP
/* Add elfcorehdr */
if (image->type == KEXEC_TYPE_CRASH) {
+ void *headers;
+ unsigned long headers_sz;
ret = prepare_elf_headers(&headers, &headers_sz);
if (ret) {
pr_err("Preparing elf core header failed\n");
@@ -264,6 +268,7 @@ static void *elf_kexec_load(struct kimage *image, char *kernel_buf,
}
cmdline = modified_cmdline;
}
+#endif

#ifdef CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY
/* Add purgatory to the image */
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 32cad6a65ccd..245919dda910 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -1358,7 +1358,7 @@ static void __init arch_reserve_crashkernel(void)
bool high = false;
int ret;

- if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;

ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
--
2.41.0


2024-01-24 05:16:59

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 13/14] arm, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on arm with some adjustments.

Here use CONFIG_CRASH_RESERVE ifdef to replace CONFIG_KEXEC ifdef.

Signed-off-by: Baoquan He <[email protected]>
---
v2->v3:
- Fix the lkp reported issue by using CONFIG_CRASH_RESERVE ifdef,
giving up the earlier IS_ENABLED(CONFIG_CRASH_RESERVE) checking
in v2.

arch/arm/kernel/setup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index ff2299ce1ad7..7b33b157fca0 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -979,7 +979,7 @@ static int __init init_machine_late(void)
}
late_initcall(init_machine_late);

-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_CRASH_RESERVE
/*
* The crash region must be aligned to 128MB to avoid
* zImage relocating below the reserved region.
@@ -1066,7 +1066,7 @@ static void __init reserve_crashkernel(void)
}
#else
static inline void reserve_crashkernel(void) {}
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_CRASH_RESERVE*/

void __init hyp_mode_check(void)
{
--
2.41.0


2024-01-24 05:17:08

by Baoquan He

[permalink] [raw]
Subject: [PATCH linux-next v3 14/14] loongarch, crash: wrap crash dumping code into crash related ifdefs

Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on loongarch with some adjustments.

Here use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
in the crashkernel reservation code.

Signed-off-by: Baoquan He <[email protected]>
---
v2->v3:
- Update code change regarding below commit:
commit 78de91b45860 ("LoongArch: Use generic interface to support crashkernel=X,[high,low]")

arch/loongarch/kernel/setup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index edf2bba80130..57d37dd9f964 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -260,7 +260,7 @@ static void __init arch_reserve_crashkernel(void)
char *cmdline = boot_command_line;
bool high = false;

- if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;

ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
--
2.41.0


Subject: Re: [PATCH linux-next v3 10/14] sh, crash: wrap crash dumping code into crash related ifdefs

Hello Baoquan,

On Wed, 2024-01-24 at 13:12 +0800, Baoquan He wrote:
> Now crash codes under kernel/ folder has been split out from kexec
> code, crash dumping can be separated from kexec reboot in config
> items on SuperH with some adjustments.
>
> wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery, and
> use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
> in the crashkernel reservation code.

Comparing this to the patches, it seems you missed the first word
"Here". Either amend that or write the word "wrap" capitalized.

I would omit "Here" as it's not necessary and just start the
sentence with "Wrap".

Adrian

--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer
`. `' Physicist
`- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913

2024-01-24 15:19:39

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 10/14] sh, crash: wrap crash dumping code into crash related ifdefs

On 01/24/24 at 09:13am, John Paul Adrian Glaubitz wrote:
> Hello Baoquan,
>
> On Wed, 2024-01-24 at 13:12 +0800, Baoquan He wrote:
> > Now crash codes under kernel/ folder has been split out from kexec
> > code, crash dumping can be separated from kexec reboot in config
> > items on SuperH with some adjustments.
> >
> > wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery, and
> > use IS_ENABLED(CONFIG_CRASH_RESERVE) check to decide if compiling
> > in the crashkernel reservation code.
>
> Comparing this to the patches, it seems you missed the first word
> "Here". Either amend that or write the word "wrap" capitalized.
>
> I would omit "Here" as it's not necessary and just start the
> sentence with "Wrap".

You are right, thanks for careful checking. I will see if I need repost
to include this update.

>
> --
> .''`. John Paul Adrian Glaubitz
> : :' : Debian Developer
> `. `' Physicist
> `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
>
> _______________________________________________
> kexec mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kexec
>


2024-01-24 23:03:10

by Michael Kelley

[permalink] [raw]
Subject: RE: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

From: Baoquan He <[email protected]> Sent: Tuesday, January 23, 2024 9:13 PM
>
> Now crash codes under kernel/ folder has been split out from kexec
> code, crash dumping can be separated from kexec reboot in config
> items on x86 with some adjustments.
>
> Here, also change some ifdefs or IS_ENABLED() check to more appropriate
> ones, e,g
> - #ifdef CONFIG_KEXEC_CORE -> #ifdef CONFIG_CRASH_DUMP
> - (!IS_ENABLED(CONFIG_KEXEC_CORE)) - >
> (!IS_ENABLED(CONFIG_CRASH_RESERVE))
>
> Signed-off-by: Baoquan He <[email protected]>
> ---
> arch/x86/kernel/Makefile | 4 ++--
> arch/x86/kernel/cpu/mshyperv.c | 4 ++++
> arch/x86/kernel/kexec-bzimage64.c | 4 ++++
> arch/x86/kernel/kvm.c | 4 ++--
> arch/x86/kernel/machine_kexec_64.c | 3 +++
> arch/x86/kernel/reboot.c | 2 +-
> arch/x86/kernel/setup.c | 2 +-
> arch/x86/kernel/smp.c | 2 +-
> arch/x86/xen/enlighten_hvm.c | 4 ++++
> 9 files changed, 22 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 913d4022131e..3668b1edef2d 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -100,9 +100,9 @@ obj-$(CONFIG_TRACING) += trace.o
> obj-$(CONFIG_RETHOOK) += rethook.o
> obj-$(CONFIG_VMCORE_INFO) += vmcore_info_$(BITS).o
> obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
> -obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
> +obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o
> obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
> -obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
> +obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o crash.o
> obj-y += kprobes/
> obj-$(CONFIG_MODULES) += module.o
> obj-$(CONFIG_X86_32) += doublefault_32.o
> diff --git a/arch/x86/kernel/cpu/mshyperv.c
> b/arch/x86/kernel/cpu/mshyperv.c
> index 01fa06dd06b6..f8163a59026b 100644
> --- a/arch/x86/kernel/cpu/mshyperv.c
> +++ b/arch/x86/kernel/cpu/mshyperv.c
> @@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
> hyperv_cleanup();
> }
>
> +#ifdef CONFIG_CRASH_DUMP
> static void hv_machine_crash_shutdown(struct pt_regs *regs)
> {
> if (hv_crash_handler)
> @@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct
> pt_regs *regs)
> /* Disable the hypercall page when there is only 1 active CPU. */
> hyperv_cleanup();
> }
> +#endif
> #endif /* CONFIG_KEXEC_CORE */

Note that the #ifdef CONFIG_CRASH_DUMP is nested inside
#ifdef CONFIG_KEXEC_CODE here, and in the other Hyper-V code
just below. It's also nested in xen_hvm_guest_init() at the bottom
of this patch. But the KVM case of setting crash_shutdown is
not nested -- you changed #ifdef CONFIG_KEXEC_CORE to #ifdef
CONFIG_CRASH_DUMP.

I think both approaches work because CONFIG_CRASH_DUMP implies
CONFIG_KEXEC_CORE, but I wonder if it would be better to *not* nest
in all cases. I'd like to see the cases be consistent so in the future
someone doesn't wonder why there's a difference (unless there's
a reason for the difference that I missed).

> #endif /* CONFIG_HYPERV */
>
> @@ -497,7 +499,9 @@ static void __init ms_hyperv_init_platform(void)
>
> #if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
> machine_ops.shutdown = hv_machine_shutdown;
> +#ifdef CONFIG_CRASH_DUMP
> machine_ops.crash_shutdown = hv_machine_crash_shutdown;
> +#endif
> #endif
> if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
> /*
> diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-
> bzimage64.c
> index 2a422e00ed4b..b55737b83a84 100644
> --- a/arch/x86/kernel/kexec-bzimage64.c
> +++ b/arch/x86/kernel/kexec-bzimage64.c
> @@ -263,11 +263,13 @@ setup_boot_parameters(struct kimage *image,
> struct boot_params *params,
> memset(&params->hd0_info, 0, sizeof(params->hd0_info));
> memset(&params->hd1_info, 0, sizeof(params->hd1_info));
>
> +#ifdef CONFIG_CRASH_DUMP
> if (image->type == KEXEC_TYPE_CRASH) {
> ret = crash_setup_memmap_entries(image, params);
> if (ret)
> return ret;
> } else
> +#endif
> setup_e820_entries(params);
>
> nr_e820_entries = params->e820_entries;
> @@ -433,12 +435,14 @@ static void *bzImage64_load(struct kimage *image, char *kernel,
> return ERR_PTR(-EINVAL);
> }
>
> +#ifdef CONFIG_CRASH_DUMP
> /* Allocate and load backup region */
> if (image->type == KEXEC_TYPE_CRASH) {
> ret = crash_load_segments(image);
> if (ret)
> return ERR_PTR(ret);
> }
> +#endif
>
> /*
> * Load purgatory. For 64bit entry point, purgatory code can be
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index dfe9945b9bec..acfc2d3183bc 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -769,7 +769,7 @@ static struct notifier_block kvm_pv_reboot_nb = {
> * won't be valid. In cases like kexec, in which you install a new kernel, this
> * means a random memory location will be kept being written.
> */
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
> static void kvm_crash_shutdown(struct pt_regs *regs)
> {
> kvm_guest_cpu_offline(true);
> @@ -852,7 +852,7 @@ static void __init kvm_guest_init(void)
> kvm_guest_cpu_init();
> #endif
>
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
> machine_ops.crash_shutdown = kvm_crash_shutdown;
> #endif
>
> diff --git a/arch/x86/kernel/machine_kexec_64.c
> b/arch/x86/kernel/machine_kexec_64.c
> index bc0a5348b4a6..b180d8e497c3 100644
> --- a/arch/x86/kernel/machine_kexec_64.c
> +++ b/arch/x86/kernel/machine_kexec_64.c
> @@ -508,6 +508,8 @@ int arch_kimage_file_post_load_cleanup(struct
> kimage *image)
> }
> #endif /* CONFIG_KEXEC_FILE */
>
> +#ifdef CONFIG_CRASH_DUMP
> +
> static int
> kexec_mark_range(unsigned long start, unsigned long end, bool protect)
> {
> @@ -552,6 +554,7 @@ void arch_kexec_unprotect_crashkres(void)
> {
> kexec_mark_crashkres(false);
> }
> +#endif
>
> /*
> * During a traditional boot under SME, SME will encrypt the kernel,
> diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
> index 830425e6d38e..1287b0d5962f 100644
> --- a/arch/x86/kernel/reboot.c
> +++ b/arch/x86/kernel/reboot.c
> @@ -796,7 +796,7 @@ struct machine_ops machine_ops __ro_after_init = {
> .emergency_restart = native_machine_emergency_restart,
> .restart = native_machine_restart,
> .halt = native_machine_halt,
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
> .crash_shutdown = native_machine_crash_shutdown,
> #endif
> };

Also in arch/x86/kernel/reboot.c, should the function
machine_crash_shutdown() be updated with
#ifdef CONFIG_CRASH_SHUTDOWN instead of #ifdef
CONFIG_KEXEC_CORE?

Michael

> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 84201071dfac..899d839a2954 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -471,7 +471,7 @@ static void __init arch_reserve_crashkernel(void)
> bool high = false;
> int ret;
>
> - if (!IS_ENABLED(CONFIG_KEXEC_CORE))
> + if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
> return;
>
> ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
> diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
> index 2908e063d7d8..18266cc3d98c 100644
> --- a/arch/x86/kernel/smp.c
> +++ b/arch/x86/kernel/smp.c
> @@ -286,7 +286,7 @@ struct smp_ops smp_ops = {
> .smp_cpus_done = native_smp_cpus_done,
>
> .stop_other_cpus = native_stop_other_cpus,
> -#if defined(CONFIG_KEXEC_CORE)
> +#if defined(CONFIG_CRASH_DUMP)
> .crash_stop_other_cpus = kdump_nmi_shootdown_cpus,
> #endif
> .smp_send_reschedule = native_smp_send_reschedule,
> diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
> index 3f8c34707c50..09e3db7ff990 100644
> --- a/arch/x86/xen/enlighten_hvm.c
> +++ b/arch/x86/xen/enlighten_hvm.c
> @@ -149,12 +149,14 @@ static void xen_hvm_shutdown(void)
> xen_reboot(SHUTDOWN_soft_reset);
> }
>
> +#ifdef CONFIG_CRASH_DUMP
> static void xen_hvm_crash_shutdown(struct pt_regs *regs)
> {
> native_machine_crash_shutdown(regs);
> xen_reboot(SHUTDOWN_soft_reset);
> }
> #endif
> +#endif
>
> static int xen_cpu_up_prepare_hvm(unsigned int cpu)
> {
> @@ -236,8 +238,10 @@ static void __init xen_hvm_guest_init(void)
>
> #ifdef CONFIG_KEXEC_CORE
> machine_ops.shutdown = xen_hvm_shutdown;
> +#ifdef CONFIG_CRASH_DUMP
> machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
> #endif
> +#endif
> }
>
> static __init int xen_parse_nopv(char *arg)
> --
> 2.41.0
>


2024-01-25 04:09:59

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

On 01/24/24 at 11:02pm, Michael Kelley wrote:
> > diff --git a/arch/x86/kernel/cpu/mshyperv.c
> > b/arch/x86/kernel/cpu/mshyperv.c
> > index 01fa06dd06b6..f8163a59026b 100644
> > --- a/arch/x86/kernel/cpu/mshyperv.c
> > +++ b/arch/x86/kernel/cpu/mshyperv.c
> > @@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
> > hyperv_cleanup();
> > }
> >
> > +#ifdef CONFIG_CRASH_DUMP
> > static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > {
> > if (hv_crash_handler)
> > @@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct
> > pt_regs *regs)
> > /* Disable the hypercall page when there is only 1 active CPU. */
> > hyperv_cleanup();
> > }
> > +#endif
> > #endif /* CONFIG_KEXEC_CORE */
>
> Note that the #ifdef CONFIG_CRASH_DUMP is nested inside
> #ifdef CONFIG_KEXEC_CODE here, and in the other Hyper-V code
> just below. It's also nested in xen_hvm_guest_init() at the bottom
> of this patch. But the KVM case of setting crash_shutdown is
> not nested -- you changed #ifdef CONFIG_KEXEC_CORE to #ifdef
> CONFIG_CRASH_DUMP.
>
> I think both approaches work because CONFIG_CRASH_DUMP implies
> CONFIG_KEXEC_CORE, but I wonder if it would be better to *not* nest
> in all cases. I'd like to see the cases be consistent so in the future
> someone doesn't wonder why there's a difference (unless there's
> a reason for the difference that I missed).

I agree with you, it's a great suggestion. Thanks.

Do you think below draft patch includes all changes you are concerned
about?

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index f8163a59026b..2e8cd5a4ae85 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -209,6 +209,7 @@ static void hv_machine_shutdown(void)
if (kexec_in_progress)
hyperv_cleanup();
}
+#endif /* CONFIG_KEXEC_CORE */

#ifdef CONFIG_CRASH_DUMP
static void hv_machine_crash_shutdown(struct pt_regs *regs)
@@ -222,8 +223,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
/* Disable the hypercall page when there is only 1 active CPU. */
hyperv_cleanup();
}
-#endif
-#endif /* CONFIG_KEXEC_CORE */
+#endif /* CONFIG_CRASH_DUMP */
#endif /* CONFIG_HYPERV */

static uint32_t __init ms_hyperv_platform(void)
@@ -497,9 +497,11 @@ static void __init ms_hyperv_init_platform(void)
no_timer_check = 1;
#endif

-#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
+#if IS_ENABLED(CONFIG_HYPERV)
+#if defined(CONFIG_KEXEC_CORE)
machine_ops.shutdown = hv_machine_shutdown;
-#ifdef CONFIG_CRASH_DUMP
+#endif
+#if defined(CONFIG_CRASH_DUMP)
machine_ops.crash_shutdown = hv_machine_crash_shutdown;
#endif
#endif
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 1287b0d5962f..f3130f762784 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -826,7 +826,7 @@ void machine_halt(void)
machine_ops.halt();
}

-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
void machine_crash_shutdown(struct pt_regs *regs)
{
machine_ops.crash_shutdown(regs);


2024-01-25 05:13:00

by Michael Kelley

[permalink] [raw]
Subject: RE: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

From: Baoquan He <[email protected]> Sent: Wednesday, January 24, 2024 8:10 PM
>
> On 01/24/24 at 11:02pm, Michael Kelley wrote:
> > > diff --git a/arch/x86/kernel/cpu/mshyperv.c
> > > b/arch/x86/kernel/cpu/mshyperv.c
> > > index 01fa06dd06b6..f8163a59026b 100644
> > > --- a/arch/x86/kernel/cpu/mshyperv.c
> > > +++ b/arch/x86/kernel/cpu/mshyperv.c
> > > @@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
> > > hyperv_cleanup();
> > > }
> > >
> > > +#ifdef CONFIG_CRASH_DUMP
> > > static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > {
> > > if (hv_crash_handler)
> > > @@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > /* Disable the hypercall page when there is only 1 active CPU. */
> > > hyperv_cleanup();
> > > }
> > > +#endif
> > > #endif /* CONFIG_KEXEC_CORE */
> >
> > Note that the #ifdef CONFIG_CRASH_DUMP is nested inside
> > #ifdef CONFIG_KEXEC_CODE here, and in the other Hyper-V code
> > just below. It's also nested in xen_hvm_guest_init() at the bottom
> > of this patch. But the KVM case of setting crash_shutdown is
> > not nested -- you changed #ifdef CONFIG_KEXEC_CORE to #ifdef
> > CONFIG_CRASH_DUMP.
> >
> > I think both approaches work because CONFIG_CRASH_DUMP implies
> > CONFIG_KEXEC_CORE, but I wonder if it would be better to *not* nest
> > in all cases. I'd like to see the cases be consistent so in the future
> > someone doesn't wonder why there's a difference (unless there's
> > a reason for the difference that I missed).
>
> I agree with you, it's a great suggestion. Thanks.
>
> Do you think below draft patch includes all changes you are concerned
> about?

Yes, these changes look good as a delta to your original patch.

But also look at xen_hvm_guest_init(). It looks like your original patch
does nesting there as well, and it could probably be "un-nested".

Michael

>
> diff --git a/arch/x86/kernel/cpu/mshyperv.c
> b/arch/x86/kernel/cpu/mshyperv.c
> index f8163a59026b..2e8cd5a4ae85 100644
> --- a/arch/x86/kernel/cpu/mshyperv.c
> +++ b/arch/x86/kernel/cpu/mshyperv.c
> @@ -209,6 +209,7 @@ static void hv_machine_shutdown(void)
> if (kexec_in_progress)
> hyperv_cleanup();
> }
> +#endif /* CONFIG_KEXEC_CORE */
>
> #ifdef CONFIG_CRASH_DUMP
> static void hv_machine_crash_shutdown(struct pt_regs *regs)
> @@ -222,8 +223,7 @@ static void hv_machine_crash_shutdown(struct
> pt_regs *regs)
> /* Disable the hypercall page when there is only 1 active CPU. */
> hyperv_cleanup();
> }
> -#endif
> -#endif /* CONFIG_KEXEC_CORE */
> +#endif /* CONFIG_CRASH_DUMP */
> #endif /* CONFIG_HYPERV */
>
> static uint32_t __init ms_hyperv_platform(void)
> @@ -497,9 +497,11 @@ static void __init ms_hyperv_init_platform(void)
> no_timer_check = 1;
> #endif
>
> -#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
> +#if IS_ENABLED(CONFIG_HYPERV)
> +#if defined(CONFIG_KEXEC_CORE)
> machine_ops.shutdown = hv_machine_shutdown;
> -#ifdef CONFIG_CRASH_DUMP
> +#endif
> +#if defined(CONFIG_CRASH_DUMP)
> machine_ops.crash_shutdown = hv_machine_crash_shutdown;
> #endif
> #endif
> diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
> index 1287b0d5962f..f3130f762784 100644
> --- a/arch/x86/kernel/reboot.c
> +++ b/arch/x86/kernel/reboot.c
> @@ -826,7 +826,7 @@ void machine_halt(void)
> machine_ops.halt();
> }
>
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
> void machine_crash_shutdown(struct pt_regs *regs)
> {
> machine_ops.crash_shutdown(regs);


2024-01-25 09:28:19

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

On 01/25/24 at 05:12am, Michael Kelley wrote:
> From: Baoquan He <[email protected]> Sent: Wednesday, January 24, 2024 8:10 PM
> >
> > On 01/24/24 at 11:02pm, Michael Kelley wrote:
> > > > diff --git a/arch/x86/kernel/cpu/mshyperv.c
> > > > b/arch/x86/kernel/cpu/mshyperv.c
> > > > index 01fa06dd06b6..f8163a59026b 100644
> > > > --- a/arch/x86/kernel/cpu/mshyperv.c
> > > > +++ b/arch/x86/kernel/cpu/mshyperv.c
> > > > @@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
> > > > hyperv_cleanup();
> > > > }
> > > >
> > > > +#ifdef CONFIG_CRASH_DUMP
> > > > static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > > {
> > > > if (hv_crash_handler)
> > > > @@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > > /* Disable the hypercall page when there is only 1 active CPU. */
> > > > hyperv_cleanup();
> > > > }
> > > > +#endif
> > > > #endif /* CONFIG_KEXEC_CORE */
> > >
> > > Note that the #ifdef CONFIG_CRASH_DUMP is nested inside
> > > #ifdef CONFIG_KEXEC_CODE here, and in the other Hyper-V code
> > > just below. It's also nested in xen_hvm_guest_init() at the bottom
> > > of this patch. But the KVM case of setting crash_shutdown is
> > > not nested -- you changed #ifdef CONFIG_KEXEC_CORE to #ifdef
> > > CONFIG_CRASH_DUMP.
> > >
> > > I think both approaches work because CONFIG_CRASH_DUMP implies
> > > CONFIG_KEXEC_CORE, but I wonder if it would be better to *not* nest
> > > in all cases. I'd like to see the cases be consistent so in the future
> > > someone doesn't wonder why there's a difference (unless there's
> > > a reason for the difference that I missed).
> >
> > I agree with you, it's a great suggestion. Thanks.
> >
> > Do you think below draft patch includes all changes you are concerned
> > about?
>
> Yes, these changes look good as a delta to your original patch.
>
> But also look at xen_hvm_guest_init(). It looks like your original patch
> does nesting there as well, and it could probably be "un-nested".

Right. I checked them all in arch/x86 this time, hope nothing is missed
again. I can post a v4 to update this x86 patch later if no other
concern. Thanks.

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index f8163a59026b..2e8cd5a4ae85 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -209,6 +209,7 @@ static void hv_machine_shutdown(void)
if (kexec_in_progress)
hyperv_cleanup();
}
+#endif /* CONFIG_KEXEC_CORE */

#ifdef CONFIG_CRASH_DUMP
static void hv_machine_crash_shutdown(struct pt_regs *regs)
@@ -222,8 +223,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
/* Disable the hypercall page when there is only 1 active CPU. */
hyperv_cleanup();
}
-#endif
-#endif /* CONFIG_KEXEC_CORE */
+#endif /* CONFIG_CRASH_DUMP */
#endif /* CONFIG_HYPERV */

static uint32_t __init ms_hyperv_platform(void)
@@ -497,9 +497,11 @@ static void __init ms_hyperv_init_platform(void)
no_timer_check = 1;
#endif

-#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
+#if IS_ENABLED(CONFIG_HYPERV)
+#if defined(CONFIG_KEXEC_CORE)
machine_ops.shutdown = hv_machine_shutdown;
-#ifdef CONFIG_CRASH_DUMP
+#endif
+#if defined(CONFIG_CRASH_DUMP)
machine_ops.crash_shutdown = hv_machine_crash_shutdown;
#endif
#endif
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 1287b0d5962f..f3130f762784 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -826,7 +826,7 @@ void machine_halt(void)
machine_ops.halt();
}

-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_DUMP
void machine_crash_shutdown(struct pt_regs *regs)
{
machine_ops.crash_shutdown(regs);
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 09e3db7ff990..0b367c1e086d 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -148,6 +148,7 @@ static void xen_hvm_shutdown(void)
if (kexec_in_progress)
xen_reboot(SHUTDOWN_soft_reset);
}
+#endif

#ifdef CONFIG_CRASH_DUMP
static void xen_hvm_crash_shutdown(struct pt_regs *regs)
@@ -156,7 +157,6 @@ static void xen_hvm_crash_shutdown(struct pt_regs *regs)
xen_reboot(SHUTDOWN_soft_reset);
}
#endif
-#endif

static int xen_cpu_up_prepare_hvm(unsigned int cpu)
{
@@ -238,10 +238,10 @@ static void __init xen_hvm_guest_init(void)

#ifdef CONFIG_KEXEC_CORE
machine_ops.shutdown = xen_hvm_shutdown;
+#endif
#ifdef CONFIG_CRASH_DUMP
machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
#endif
-#endif
}

static __init int xen_parse_nopv(char *arg)


2024-01-25 15:31:39

by Michael Kelley

[permalink] [raw]
Subject: RE: [PATCH linux-next v3 06/14] x86, crash: wrap crash dumping code into crash related ifdefs

From: Baoquan He <[email protected]> Sent: Thursday, January 25, 2024 1:17 AM
>
> On 01/25/24 at 05:12am, Michael Kelley wrote:
> > From: Baoquan He <[email protected]> Sent: Wednesday, January 24, 2024
> 8:10 PM
> > >
> > > On 01/24/24 at 11:02pm, Michael Kelley wrote:
> > > > > diff --git a/arch/x86/kernel/cpu/mshyperv.c
> > > > > b/arch/x86/kernel/cpu/mshyperv.c
> > > > > index 01fa06dd06b6..f8163a59026b 100644
> > > > > --- a/arch/x86/kernel/cpu/mshyperv.c
> > > > > +++ b/arch/x86/kernel/cpu/mshyperv.c
> > > > > @@ -210,6 +210,7 @@ static void hv_machine_shutdown(void)
> > > > > hyperv_cleanup();
> > > > > }
> > > > >
> > > > > +#ifdef CONFIG_CRASH_DUMP
> > > > > static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > > > {
> > > > > if (hv_crash_handler)
> > > > > @@ -221,6 +222,7 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
> > > > > /* Disable the hypercall page when there is only 1 active CPU. */
> > > > > hyperv_cleanup();
> > > > > }
> > > > > +#endif
> > > > > #endif /* CONFIG_KEXEC_CORE */
> > > >
> > > > Note that the #ifdef CONFIG_CRASH_DUMP is nested inside
> > > > #ifdef CONFIG_KEXEC_CODE here, and in the other Hyper-V code
> > > > just below. It's also nested in xen_hvm_guest_init() at the bottom
> > > > of this patch. But the KVM case of setting crash_shutdown is
> > > > not nested -- you changed #ifdef CONFIG_KEXEC_CORE to #ifdef
> > > > CONFIG_CRASH_DUMP.
> > > >
> > > > I think both approaches work because CONFIG_CRASH_DUMP implies
> > > > CONFIG_KEXEC_CORE, but I wonder if it would be better to *not* nest
> > > > in all cases. I'd like to see the cases be consistent so in the future
> > > > someone doesn't wonder why there's a difference (unless there's
> > > > a reason for the difference that I missed).
> > >
> > > I agree with you, it's a great suggestion. Thanks.
> > >
> > > Do you think below draft patch includes all changes you are concerned
> > > about?
> >
> > Yes, these changes look good as a delta to your original patch.
> >
> > But also look at xen_hvm_guest_init(). It looks like your original patch
> > does nesting there as well, and it could probably be "un-nested".
>
> Right. I checked them all in arch/x86 this time, hope nothing is missed
> again. I can post a v4 to update this x86 patch later if no other
> concern. Thanks.

Yes -- everything looks good to me now.

Michael

>
> diff --git a/arch/x86/kernel/cpu/mshyperv.c
> b/arch/x86/kernel/cpu/mshyperv.c
> index f8163a59026b..2e8cd5a4ae85 100644
> --- a/arch/x86/kernel/cpu/mshyperv.c
> +++ b/arch/x86/kernel/cpu/mshyperv.c
> @@ -209,6 +209,7 @@ static void hv_machine_shutdown(void)
> if (kexec_in_progress)
> hyperv_cleanup();
> }
> +#endif /* CONFIG_KEXEC_CORE */
>
> #ifdef CONFIG_CRASH_DUMP
> static void hv_machine_crash_shutdown(struct pt_regs *regs)
> @@ -222,8 +223,7 @@ static void hv_machine_crash_shutdown(struct
> pt_regs *regs)
> /* Disable the hypercall page when there is only 1 active CPU. */
> hyperv_cleanup();
> }
> -#endif
> -#endif /* CONFIG_KEXEC_CORE */
> +#endif /* CONFIG_CRASH_DUMP */
> #endif /* CONFIG_HYPERV */
>
> static uint32_t __init ms_hyperv_platform(void)
> @@ -497,9 +497,11 @@ static void __init ms_hyperv_init_platform(void)
> no_timer_check = 1;
> #endif
>
> -#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
> +#if IS_ENABLED(CONFIG_HYPERV)
> +#if defined(CONFIG_KEXEC_CORE)
> machine_ops.shutdown = hv_machine_shutdown;
> -#ifdef CONFIG_CRASH_DUMP
> +#endif
> +#if defined(CONFIG_CRASH_DUMP)
> machine_ops.crash_shutdown = hv_machine_crash_shutdown;
> #endif
> #endif
> diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
> index 1287b0d5962f..f3130f762784 100644
> --- a/arch/x86/kernel/reboot.c
> +++ b/arch/x86/kernel/reboot.c
> @@ -826,7 +826,7 @@ void machine_halt(void)
> machine_ops.halt();
> }
>
> -#ifdef CONFIG_KEXEC_CORE
> +#ifdef CONFIG_CRASH_DUMP
> void machine_crash_shutdown(struct pt_regs *regs)
> {
> machine_ops.crash_shutdown(regs);
> diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
> index 09e3db7ff990..0b367c1e086d 100644
> --- a/arch/x86/xen/enlighten_hvm.c
> +++ b/arch/x86/xen/enlighten_hvm.c
> @@ -148,6 +148,7 @@ static void xen_hvm_shutdown(void)
> if (kexec_in_progress)
> xen_reboot(SHUTDOWN_soft_reset);
> }
> +#endif
>
> #ifdef CONFIG_CRASH_DUMP
> static void xen_hvm_crash_shutdown(struct pt_regs *regs)
> @@ -156,7 +157,6 @@ static void xen_hvm_crash_shutdown(struct pt_regs
> *regs)
> xen_reboot(SHUTDOWN_soft_reset);
> }
> #endif
> -#endif
>
> static int xen_cpu_up_prepare_hvm(unsigned int cpu)
> {
> @@ -238,10 +238,10 @@ static void __init xen_hvm_guest_init(void)
>
> #ifdef CONFIG_KEXEC_CORE
> machine_ops.shutdown = xen_hvm_shutdown;
> +#endif
> #ifdef CONFIG_CRASH_DUMP
> machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
> #endif
> -#endif
> }
>
> static __init int xen_parse_nopv(char *arg)


2024-01-26 05:01:36

by Nathan Chancellor

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 00/14] Split crash out from kexec and clean up related config items

Hi Baoquan,

On Wed, Jan 24, 2024 at 01:12:40PM +0800, Baoquan He wrote:
> Motivation:
> =============
> Previously, LKP reported a building error. When investigating, it can't
> be resolved reasonablly with the present messy kdump config items.
>
> https://lore.kernel.org/oe-kbuild-all/[email protected]/
>
> The kdump (crash dumping) related config items could causes confusions:
>
> Firstly,
> ---
> CRASH_CORE enables codes including
> - crashkernel reservation;
> - elfcorehdr updating;
> - vmcoreinfo exporting;
> - crash hotplug handling;
>
> Now fadump of powerpc, kcore dynamic debugging and kdump all selects
> CRASH_CORE, while fadump
> - fadump needs crashkernel parsing, vmcoreinfo exporting, and accessing
> global variable 'elfcorehdr_addr';
> - kcore only needs vmcoreinfo exporting;
> - kdump needs all of the current kernel/crash_core.c.
>
> So only enabling PROC_CORE or FA_DUMP will enable CRASH_CORE, this
> mislead people that we enable crash dumping, actual it's not.
>
> Secondly,
> ---
> It's not reasonable to allow KEXEC_CORE select CRASH_CORE.
>
> Because KEXEC_CORE enables codes which allocate control pages, copy
> kexec/kdump segments, and prepare for switching. These codes are
> shared by both kexec reboot and kdump. We could want kexec reboot,
> but disable kdump. In that case, CRASH_CORE should not be selected.
>
> --------------------
> CONFIG_CRASH_CORE=y
> CONFIG_KEXEC_CORE=y
> CONFIG_KEXEC=y
> CONFIG_KEXEC_FILE=y
> ---------------------
>
> Thirdly,
> ---
> It's not reasonable to allow CRASH_DUMP select KEXEC_CORE.
>
> That could make KEXEC_CORE, CRASH_DUMP are enabled independently from
> KEXEC or KEXEC_FILE. However, w/o KEXEC or KEXEC_FILE, the KEXEC_CORE
> code built in doesn't make any sense because no kernel loading or
> switching will happen to utilize the KEXEC_CORE code.
> ---------------------
> CONFIG_CRASH_CORE=y
> CONFIG_KEXEC_CORE=y
> CONFIG_CRASH_DUMP=y
> ---------------------
>
> In this case, what is worse, on arch sh and arm, KEXEC relies on MMU,
> while CRASH_DUMP can still be enabled when !MMU, then compiling error is
> seen as the lkp test robot reported in above link.
>
> ------arch/sh/Kconfig------
> config ARCH_SUPPORTS_KEXEC
> def_bool MMU
>
> config ARCH_SUPPORTS_CRASH_DUMP
> def_bool BROKEN_ON_SMP
> ---------------------------
>
> Changes:
> ===========
> 1, split out crash_reserve.c from crash_core.c;
> 2, split out vmcore_infoc. from crash_core.c;
> 3, move crash related codes in kexec_core.c into crash_core.c;
> 4, remove dependency of FA_DUMP on CRASH_DUMP;
> 5, clean up kdump related config items;
> 6, wrap up crash codes in crash related ifdefs on all 8 arch-es
> which support crash dumping, except of ppc;
>
> Achievement:
> ===========
> With above changes, I can rearrange the config item logic as below (the right
> item depends on or is selected by the left item):
>
> PROC_KCORE -----------> VMCORE_INFO
>
> |----------> VMCORE_INFO
> FA_DUMP----|
> |----------> CRASH_RESERVE
>
> ---->VMCORE_INFO
> /
> |---->CRASH_RESERVE
> KEXEC --| /|
> |--> KEXEC_CORE--> CRASH_DUMP-->/-|---->PROC_VMCORE
> KEXEC_FILE --| \ |
> \---->CRASH_HOTPLUG
>
>
> KEXEC --|
> |--> KEXEC_CORE (for kexec reboot only)
> KEXEC_FILE --|
>
> Test
> ========
> On all 8 architectures, including x86_64, arm64, s390x, sh, arm, mips,
> riscv, loongarch, I did below three cases of config item setting and
> building all passed. Take configs on x86_64 as exampmle here:
>
> (1) Both CONFIG_KEXEC and KEXEC_FILE is unset, then all kexec/kdump
> items are unset automatically:
> # Kexec and crash features
> # CONFIG_KEXEC is not set
> # CONFIG_KEXEC_FILE is not set
> # end of Kexec and crash features
>
> (2) set CONFIG_KEXEC_FILE and 'make olddefconfig':
> ---------------
> # Kexec and crash features
> CONFIG_CRASH_RESERVE=y
> CONFIG_VMCORE_INFO=y
> CONFIG_KEXEC_CORE=y
> CONFIG_KEXEC_FILE=y
> CONFIG_CRASH_DUMP=y
> CONFIG_CRASH_HOTPLUG=y
> CONFIG_CRASH_MAX_MEMORY_RANGES=8192
> # end of Kexec and crash features
> ---------------
>
> (3) unset CONFIG_CRASH_DUMP in case 2 and execute 'make olddefconfig':
> ------------------------
> # Kexec and crash features
> CONFIG_KEXEC_CORE=y
> CONFIG_KEXEC_FILE=y
> # end of Kexec and crash features
> ------------------------
>
> Note:
> For ppc, it needs investigation to make clear how to split out crash
> code in arch folder. Hope Hari and Pingfan can help have a look, see if
> it's doable. Now, I make it either have both kexec and crash enabled, or
> disable both of them altogether.

I am seeing a few build failures in my test matrix on next-20240125 that
appear to be caused by this series although I have not bisected. Some
reproduction steps:

$ curl -LSso .config https://git.alpinelinux.org/aports/plain/community/linux-edge/config-edge.armv7
$ make -skj"$(nproc)" ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- olddefconfig all
..
arm-linux-gnueabi-ld: arch/arm/kernel/machine_kexec.o: in function `arch_crash_save_vmcoreinfo':
machine_kexec.c:(.text+0x488): undefined reference to `vmcoreinfo_append_str'
..

$ curl -LSso .config https://github.com/archlinuxarm/PKGBUILDs/raw/master/core/linux-aarch64/config
$ make -skj"$(nproc)" ARCH=arm64 CROSS_COMPILE=aarch64-linux- olddefconfig all
..
aarch64-linux-ld: kernel/kexec_file.o: in function `kexec_walk_memblock.constprop.0':
kexec_file.c:(.text+0x314): undefined reference to `crashk_res'
aarch64-linux-ld: kernel/kexec_file.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
kexec_file.c:(.text+0x314): dangerous relocation: unsupported relocation
aarch64-linux-ld: kexec_file.c:(.text+0x318): undefined reference to `crashk_res'
aarch64-linux-ld: drivers/of/kexec.o: in function `of_kexec_alloc_and_setup_fdt':
kexec.c:(.text+0x580): undefined reference to `crashk_res'
aarch64-linux-ld: drivers/of/kexec.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
kexec.c:(.text+0x580): dangerous relocation: unsupported relocation
aarch64-linux-ld: kexec.c:(.text+0x584): undefined reference to `crashk_res'
aarch64-linux-ld: kexec.c:(.text+0x590): undefined reference to `crashk_res'
aarch64-linux-ld: kexec.c:(.text+0x5b0): undefined reference to `crashk_low_res'
aarch64-linux-ld: drivers/of/kexec.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_low_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
kexec.c:(.text+0x5b0): dangerous relocation: unsupported relocation
aarch64-linux-ld: kexec.c:(.text+0x5b4): undefined reference to `crashk_low_res'
aarch64-linux-ld: kexec.c:(.text+0x5c0): undefined reference to `crashk_low_res'
..

$ curl -LSso .config https://git.alpinelinux.org/aports/plain/community/linux-edge/config-edge.x86_64
$ make -skj"$(nproc)" ARCH=x86_64 CROSS_COMPILE=x86_64-linux- olddefconfig all
..
x86_64-linux-ld: arch/x86/xen/mmu_pv.o: in function `paddr_vmcoreinfo_note':
mmu_pv.c:(.text+0x3af3): undefined reference to `vmcoreinfo_note'
..

Cheers,
Nathan

2024-01-26 06:16:34

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 00/14] Split crash out from kexec and clean up related config items

On 01/25/24 at 09:55pm, Nathan Chancellor wrote:
.....
> I am seeing a few build failures in my test matrix on next-20240125 that
> appear to be caused by this series although I have not bisected. Some
> reproduction steps:

Thanks for trying this, I have reproduced the linking failure on arm,
will work out a way to fix it.

It's weird, I remember I have built these and passed.

>
> $ curl -LSso .config https://git.alpinelinux.org/aports/plain/community/linux-edge/config-edge.armv7
> $ make -skj"$(nproc)" ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- olddefconfig all
> ...
> arm-linux-gnueabi-ld: arch/arm/kernel/machine_kexec.o: in function `arch_crash_save_vmcoreinfo':
> machine_kexec.c:(.text+0x488): undefined reference to `vmcoreinfo_append_str'
> ...
>
> $ curl -LSso .config https://github.com/archlinuxarm/PKGBUILDs/raw/master/core/linux-aarch64/config
> $ make -skj"$(nproc)" ARCH=arm64 CROSS_COMPILE=aarch64-linux- olddefconfig all
> ...
> aarch64-linux-ld: kernel/kexec_file.o: in function `kexec_walk_memblock.constprop.0':
> kexec_file.c:(.text+0x314): undefined reference to `crashk_res'
> aarch64-linux-ld: kernel/kexec_file.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
> kexec_file.c:(.text+0x314): dangerous relocation: unsupported relocation
> aarch64-linux-ld: kexec_file.c:(.text+0x318): undefined reference to `crashk_res'
> aarch64-linux-ld: drivers/of/kexec.o: in function `of_kexec_alloc_and_setup_fdt':
> kexec.c:(.text+0x580): undefined reference to `crashk_res'
> aarch64-linux-ld: drivers/of/kexec.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
> kexec.c:(.text+0x580): dangerous relocation: unsupported relocation
> aarch64-linux-ld: kexec.c:(.text+0x584): undefined reference to `crashk_res'
> aarch64-linux-ld: kexec.c:(.text+0x590): undefined reference to `crashk_res'
> aarch64-linux-ld: kexec.c:(.text+0x5b0): undefined reference to `crashk_low_res'
> aarch64-linux-ld: drivers/of/kexec.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `crashk_low_res' which may bind externally can not be used when making a shared object; recompile with -fPIC
> kexec.c:(.text+0x5b0): dangerous relocation: unsupported relocation
> aarch64-linux-ld: kexec.c:(.text+0x5b4): undefined reference to `crashk_low_res'
> aarch64-linux-ld: kexec.c:(.text+0x5c0): undefined reference to `crashk_low_res'
> ...
>
> $ curl -LSso .config https://git.alpinelinux.org/aports/plain/community/linux-edge/config-edge.x86_64
> $ make -skj"$(nproc)" ARCH=x86_64 CROSS_COMPILE=x86_64-linux- olddefconfig all
> ...
> x86_64-linux-ld: arch/x86/xen/mmu_pv.o: in function `paddr_vmcoreinfo_note':
> mmu_pv.c:(.text+0x3af3): undefined reference to `vmcoreinfo_note'
> ...
>
> Cheers,
> Nathan
>


2024-01-28 01:28:43

by Klara Modin

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 01/14] kexec: split crashkernel reservation code out from crash_core.c

Hi,

On 2024-01-24 06:12, Baoquan He wrote:
> And also add config item CRASH_RESERVE to control its enabling of the
> codes. And update config items which has relationship with crashkernel
> reservation.
>
> And also change ifdeffery from CONFIG_CRASH_CORE to CONFIG_CRASH_RESERVE
> when those scopes are only crashkernel reservation related.

> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 502986237cb6..a9243e0948a3 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -2106,7 +2106,7 @@ config ARCH_SUPPORTS_CRASH_HOTPLUG
> def_bool y
>
> config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
> - def_bool CRASH_CORE
> + def_bool CRASH_RESEERVE
>
> config PHYSICAL_START
> hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)

CRASH_RESEERVE is probably a typo and should be CRASH_RESERVE (with the
former ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION isn't defined in my
config and `crashkernel=...` parameter has no effect).

Kind regards,
Klara Modin

2024-01-29 01:58:14

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 01/14] kexec: split crashkernel reservation code out from crash_core.c

On 01/28/24 at 02:28am, Klara Modin wrote:
> Hi,
>
> On 2024-01-24 06:12, Baoquan He wrote:
> > And also add config item CRASH_RESERVE to control its enabling of the
> > codes. And update config items which has relationship with crashkernel
> > reservation.
> >
> > And also change ifdeffery from CONFIG_CRASH_CORE to CONFIG_CRASH_RESERVE
> > when those scopes are only crashkernel reservation related.
>
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 502986237cb6..a9243e0948a3 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -2106,7 +2106,7 @@ config ARCH_SUPPORTS_CRASH_HOTPLUG
> > def_bool y
> > config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
> > - def_bool CRASH_CORE
> > + def_bool CRASH_RESEERVE
> > config PHYSICAL_START
> > hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
>
> CRASH_RESEERVE is probably a typo and should be CRASH_RESERVE (with the
> former ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION isn't defined in my .config
> and `crashkernel=...` parameter has no effect).

You are right, thanks a lot. Will fix that.


2024-03-25 13:55:51

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 02/14] crash: split vmcoreinfo exporting code out from crash_core.c

Hi Baoquan,

On Wed, Jan 24, 2024 at 6:13 AM Baoquan He <[email protected]> wrote:
> Now move the relevant codes into separate files:
> kernel/crash_reserve.c, include/linux/crash_reserve.h.
>
> And add config item CRASH_RESERVE to control its enabling.
>
> And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
> <linux/crash_core.h> and config item dependency on CRASH_CORE
> accordingly.
>
> And also do renaming as follows:
> - arch/xxx/kernel/{crash_core.c => vmcore_info.c}
> because they are only related to vmcoreinfo exporting on x86, arm64,
> riscv.
>
> And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
> decide if build in crash_core.c.
>
> Signed-off-by: Baoquan He <[email protected]>
> ---
> v2->v3:
> - There's conflict when rebasing to linux-next in kernel/crash_core.c
> because of below commits from Uladzislau:
> commit 699d9351822e ("mm: vmalloc: Fix a warning in the crash_save_vmcoreinfo_init()")
> commit 5f4c0c1e2a51 (:mm/vmalloc: remove vmap_area_list")

Thanks for your patch, which is now commit 443cbaf9e2fdbef7
("crash: split vmcoreinfo exporting code out from
crash_core.c") in v6.9-rc1.

After this, there are still two references left to CRASH_CORE:

1. Documentation/admin-guide/kdump/kdump.rst:

Subsequently, CRASH_CORE is selected by KEXEC_CORE::

2. arch/loongarch/Kconfig

config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
def_bool CRASH_CORE

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

2024-03-25 14:09:05

by Baoquan He

[permalink] [raw]
Subject: Re: [PATCH linux-next v3 02/14] crash: split vmcoreinfo exporting code out from crash_core.c

On 03/25/24 at 09:24am, Geert Uytterhoeven wrote:
> Hi Baoquan,
>
> On Wed, Jan 24, 2024 at 6:13 AM Baoquan He <[email protected]> wrote:
> > Now move the relevant codes into separate files:
> > kernel/crash_reserve.c, include/linux/crash_reserve.h.
> >
> > And add config item CRASH_RESERVE to control its enabling.
> >
> > And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
> > <linux/crash_core.h> and config item dependency on CRASH_CORE
> > accordingly.
> >
> > And also do renaming as follows:
> > - arch/xxx/kernel/{crash_core.c => vmcore_info.c}
> > because they are only related to vmcoreinfo exporting on x86, arm64,
> > riscv.
> >
> > And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
> > decide if build in crash_core.c.
> >
> > Signed-off-by: Baoquan He <[email protected]>
> > ---
> > v2->v3:
> > - There's conflict when rebasing to linux-next in kernel/crash_core.c
> > because of below commits from Uladzislau:
> > commit 699d9351822e ("mm: vmalloc: Fix a warning in the crash_save_vmcoreinfo_init()")
> > commit 5f4c0c1e2a51 (:mm/vmalloc: remove vmap_area_list")
>
> Thanks for your patch, which is now commit 443cbaf9e2fdbef7
> ("crash: split vmcoreinfo exporting code out from
> crash_core.c") in v6.9-rc1.
>
> After this, there are still two references left to CRASH_CORE:
>
> 1. Documentation/admin-guide/kdump/kdump.rst:
>
> Subsequently, CRASH_CORE is selected by KEXEC_CORE::
>
> 2. arch/loongarch/Kconfig
>
> config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
> def_bool CRASH_CORE

Sure, will post patch to clean them up. Thanks a lot.