Now there's two kexec load syscall, one is kexec_load another is
kexec_file_load, kexec_file_load has been splited as kernel/kexec_file.c.
In this patch I split kexec_load syscall code to kernel/kexec.c.
And add a new kconfig option KEXEC_CORE, so we can disable kexec_load
and use kexec_file_load only, or vice verse.
The original requirement is from Tedso, he want kexec kernel signature being
checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use kexec_load
syscall can bypass the checking.
Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.
Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig. Also updated general kernel code with
to kexec_load syscall.
Signed-off-by: Dave Young <[email protected]>
---
arch/arm/Kconfig | 4 +
arch/ia64/Kconfig | 4 +
arch/m68k/Kconfig | 4 +
arch/mips/Kconfig | 4 +
arch/powerpc/Kconfig | 4 +
arch/sh/Kconfig | 4 +
arch/tile/Kconfig | 4 +
arch/x86/Kconfig | 6 +-
arch/x86/boot/header.S | 2 +-
arch/x86/include/asm/kdebug.h | 2 +-
arch/x86/kernel/Makefile | 4 +-
arch/x86/kernel/kvmclock.c | 4 +-
arch/x86/kernel/reboot.c | 4 +-
arch/x86/kernel/setup.c | 2 +-
arch/x86/kernel/vmlinux.lds.S | 2 +-
arch/x86/kvm/vmx.c | 8 +-
arch/x86/platform/efi/efi.c | 4 +-
arch/x86/platform/uv/uv_nmi.c | 6 +-
drivers/firmware/efi/Kconfig | 2 +-
drivers/pci/pci-driver.c | 2 +-
include/linux/kexec.h | 12 +-
init/initramfs.c | 4 +-
kernel/Makefile | 1 +
kernel/events/core.c | 2 +-
kernel/kexec.c | 1578 +---------------------------------------
kernel/kexec_core.c | 1594 +++++++++++++++++++++++++++++++++++++++++
kernel/ksysfs.c | 6 +-
kernel/printk/printk.c | 2 +-
kernel/reboot.c | 2 +-
kernel/sysctl.c | 2 +-
30 files changed, 1668 insertions(+), 1611 deletions(-)
create mode 100644 kernel/kexec_core.c
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 1c50210..20c48b3 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
be linked for and stored to. This address is dependent on your
own flash usage.
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "Kexec system call (EXPERIMENTAL)"
depends on (!SMP || PM_SLEEP_SMP)
depends on !CPU_V7M
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 42a91a7..7db8fb7 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -515,9 +515,13 @@ config IA64_HP_AML_NFW
source "drivers/sn/Kconfig"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on !IA64_HP_SIM && (!SMP || HOTPLUG_CPU)
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 2dd8f63..875c518 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -92,9 +92,13 @@ config MMU_SUN3
bool
depends on MMU && !MMU_MOTOROLA && !MMU_COLDFIRE
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on M68KCLASSIC
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 2a14585..0084fb6 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2594,8 +2594,12 @@ config SCHED_HRTICK
source "kernel/Kconfig.preempt"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "Kexec system call"
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 5ef2711..68d6674 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -412,9 +412,13 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
default "y" if PPC_POWERNV
select ARCH_SUPPORTS_MEMORY_FAILURE
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP))
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 50057fe..9edd1cc 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -599,9 +599,13 @@ menu "Kernel features"
source kernel/Kconfig.hz
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on SUPERH32 && MMU
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 9def1f5..aa533a7 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -202,8 +202,12 @@ endif
source "kernel/Kconfig.hz"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
+ select KEXEC_CORE
---help---
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 55bced1..290a912 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1716,8 +1716,12 @@ config SECCOMP
source kernel/Kconfig.hz
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
+ select KEXEC_CORE
---help---
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
@@ -1734,8 +1738,8 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
+ select KEXEC_CORE
select BUILD_BIN2C
- depends on KEXEC
depends on X86_64
depends on CRYPTO=y
depends on CRYPTO_SHA256=y
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 16ef025..2d6b309 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -414,7 +414,7 @@ xloadflags:
# define XLF23 0
#endif
-#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC)
+#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC_CORE)
# define XLF4 XLF_EFI_KEXEC
#else
# define XLF4 0
diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h
index 32ce713..b130d59 100644
--- a/arch/x86/include/asm/kdebug.h
+++ b/arch/x86/include/asm/kdebug.h
@@ -29,7 +29,7 @@ extern void show_trace(struct task_struct *t, struct pt_regs *regs,
extern void __show_regs(struct pt_regs *regs, int all);
extern unsigned long oops_begin(void);
extern void oops_end(unsigned long, struct pt_regs *, int signr);
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
extern int in_crash_kexec;
#else
/* no crash dump is ever in progress if no crash kernel can be kexec'd */
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0f15af4..d538d42 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -69,8 +69,8 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_X86_TSC) += trace_clock.o
-obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
-obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o
+obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
+obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
obj-y += kprobes/
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 49487b4..2c7aafa 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -200,7 +200,7 @@ static void kvm_setup_secondary_clock(void)
* kind of shutdown from our side, we unregister the clock by writting anything
* that does not have the 'enable' bit set in the msr
*/
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
static void kvm_crash_shutdown(struct pt_regs *regs)
{
native_write_msr(msr_kvm_system_time, 0, 0);
@@ -259,7 +259,7 @@ void __init kvmclock_init(void)
x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
machine_ops.shutdown = kvm_shutdown;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
machine_ops.crash_shutdown = kvm_crash_shutdown;
#endif
kvm_get_preset_lpj();
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 86db4bc..02693dd 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -673,7 +673,7 @@ struct machine_ops machine_ops = {
.emergency_restart = native_machine_emergency_restart,
.restart = native_machine_restart,
.halt = native_machine_halt,
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
.crash_shutdown = native_machine_crash_shutdown,
#endif
};
@@ -703,7 +703,7 @@ void machine_halt(void)
machine_ops.halt();
}
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
void machine_crash_shutdown(struct pt_regs *regs)
{
machine_ops.crash_shutdown(regs);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 80f874b..1c0faa7 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -498,7 +498,7 @@ static void __init memblock_x86_reserve_range_setup_data(void)
* --------- Crashkernel reservation ------------------------------
*/
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* Keep the crash kernel below this limit. On 32 bits earlier kernels
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 00bf300..74e4bf1 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -364,7 +364,7 @@ INIT_PER_CPU(irq_stack_union);
#endif /* CONFIG_X86_32 */
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
#include <asm/kexec.h>
. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e856dd5..32e61e9 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1264,7 +1264,7 @@ static void vmcs_load(struct vmcs *vmcs)
vmcs, phys_addr);
}
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* This bitmap is used to indicate whether the vmclear
* operation is enabled on all cpus. All disabled by
@@ -1302,7 +1302,7 @@ static void crash_vmclear_local_loaded_vmcss(void)
#else
static inline void crash_enable_local_vmclear(int cpu) { }
static inline void crash_disable_local_vmclear(int cpu) { }
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
static void __loaded_vmcs_clear(void *arg)
{
@@ -10430,7 +10430,7 @@ static int __init vmx_init(void)
if (r)
return r;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
rcu_assign_pointer(crash_vmclear_loaded_vmcss,
crash_vmclear_local_loaded_vmcss);
#endif
@@ -10440,7 +10440,7 @@ static int __init vmx_init(void)
static void __exit vmx_exit(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
synchronize_rcu();
#endif
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index cfba30f..f1e5419 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -650,7 +650,7 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)
static void __init save_runtime_map(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *tmp, *p, *q = NULL;
int count = 0;
@@ -748,7 +748,7 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
static void __init kexec_enter_virtual_mode(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *p;
diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c
index 020c101..5c9f63f 100644
--- a/arch/x86/platform/uv/uv_nmi.c
+++ b/arch/x86/platform/uv/uv_nmi.c
@@ -492,7 +492,7 @@ static void uv_nmi_touch_watchdogs(void)
touch_nmi_watchdog();
}
-#if defined(CONFIG_KEXEC)
+#if defined(CONFIG_KEXEC_CORE)
static atomic_t uv_nmi_kexec_failed;
static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
@@ -519,13 +519,13 @@ static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
uv_nmi_sync_exit(0);
}
-#else /* !CONFIG_KEXEC */
+#else /* !CONFIG_KEXEC_CORE */
static inline void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
if (master)
pr_err("UV: NMI kdump: KEXEC not supported in this kernel\n");
}
-#endif /* !CONFIG_KEXEC */
+#endif /* !CONFIG_KEXEC_CORE */
#ifdef CONFIG_KGDB
#ifdef CONFIG_KGDB_KDB
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 54071c1..84533e0 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -43,7 +43,7 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE
config EFI_RUNTIME_MAP
bool "Export efi runtime maps to sysfs"
- depends on X86 && EFI && KEXEC
+ depends on X86 && EFI && KEXEC_CORE
default y
help
Export efi runtime memory maps to /sys/firmware/efi/runtime-map.
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 3cb2210..2bf9532 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -453,7 +453,7 @@ static void pci_device_shutdown(struct device *dev)
pci_msi_shutdown(pci_dev);
pci_msix_shutdown(pci_dev);
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* If this is a kexec reboot, turn off Bus Master bit on the
* device to tell it to not continue to do DMA. Don't touch
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index e804306..79c1bca 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -16,7 +16,7 @@
#include <uapi/linux/kexec.h>
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
#include <linux/linkage.h>
#include <linux/compat.h>
@@ -318,12 +318,18 @@ int crash_shrink_memory(unsigned long new_size);
size_t crash_get_memory_size(void);
void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
-#else /* !CONFIG_KEXEC */
+#ifdef CONFIG_KEXEC
+int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments,
+ unsigned long flags);
+#endif
+#else /* !CONFIG_KEXEC_CORE */
struct pt_regs;
struct task_struct;
static inline void crash_kexec(struct pt_regs *regs) { }
static inline int kexec_should_crash(struct task_struct *p) { return 0; }
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
#endif /* !defined(__ASSEBMLY__) */
diff --git a/init/initramfs.c b/init/initramfs.c
index ad1bd77..b32ad7d 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -526,14 +526,14 @@ extern unsigned long __initramfs_size;
static void __init free_initrd(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
unsigned long crashk_end = (unsigned long)__va(crashk_res.end);
#endif
if (do_retain_initrd)
goto skip;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* If the initrd region is overlapped with crashkernel reserved region,
* free only memory that is not part of crashkernel region.
diff --git a/kernel/Makefile b/kernel/Makefile
index f178fe4..af9708d 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_MODULE_SIG) += module_signing.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
+obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d3dae34..a9a6bc1 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8872,7 +8872,7 @@ static void perf_event_init_cpu(int cpu)
mutex_unlock(&swhash->hlist_mutex);
}
-#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC
+#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE
static void __perf_event_exit_context(void *__info)
{
struct remove_event re = { .detach_group = true };
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 641b2db..6c48d1c 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1,938 +1,20 @@
/*
- * kexec.c - kexec system call
+ * kexec.c - kexec_load system call
* Copyright (C) 2002-2004 Eric Biederman <[email protected]>
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*/
-#define pr_fmt(fmt) "kexec: " fmt
-
#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/file.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
#include <linux/kexec.h>
#include <linux/mutex.h>
#include <linux/list.h>
-#include <linux/highmem.h>
#include <linux/syscalls.h>
-#include <linux/reboot.h>
-#include <linux/ioport.h>
-#include <linux/hardirq.h>
-#include <linux/elf.h>
-#include <linux/elfcore.h>
-#include <linux/utsname.h>
-#include <linux/numa.h>
-#include <linux/suspend.h>
-#include <linux/device.h>
-#include <linux/freezer.h>
-#include <linux/pm.h>
-#include <linux/cpu.h>
-#include <linux/console.h>
-#include <linux/swap.h>
-#include <linux/syscore_ops.h>
-#include <linux/compiler.h>
-#include <linux/hugetlb.h>
-
-#include <asm/page.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
-#include <asm/sections.h>
-
-#include <crypto/hash.h>
-#include <crypto/sha.h>
#include "kexec_internal.h"
-DEFINE_MUTEX(kexec_mutex);
-
-/* Per cpu memory for storing cpu states in case of system crash. */
-note_buf_t __percpu *crash_notes;
-
-/* vmcoreinfo stuff */
-static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
-u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
-size_t vmcoreinfo_size;
-size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
-
-/* Flag to indicate we are going to kexec a new kernel */
-bool kexec_in_progress = false;
-
-
-/* Location of the reserved area for the crash kernel */
-struct resource crashk_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_MEM
-};
-struct resource crashk_low_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_MEM
-};
-
-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 do_exit() 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;
-}
-
-/*
- * When kexec transitions to the new kernel there is a one-to-one
- * mapping between physical and virtual addresses. On processors
- * where you can disable the MMU this is trivial, and easy. For
- * others it is still a simple predictable page table to setup.
- *
- * In that environment kexec copies the new kernel to its final
- * resting place. This means I can only support memory whose
- * physical address can fit in an unsigned long. In particular
- * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled.
- * If the assembly stub has more restrictive requirements
- * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be
- * defined more restrictively in <asm/kexec.h>.
- *
- * The code for the transition from the current kernel to the
- * the new kernel is placed in the control_code_buffer, whose size
- * is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single
- * page of memory is necessary, but some architectures require more.
- * Because this memory must be identity mapped in the transition from
- * virtual to physical addresses it must live in the range
- * 0 - TASK_SIZE, as only the user space mappings are arbitrarily
- * modifiable.
- *
- * The assembly stub in the control code buffer is passed a linked list
- * of descriptor pages detailing the source pages of the new kernel,
- * and the destination addresses of those source pages. As this data
- * structure is not used in the context of the current OS, it must
- * be self-contained.
- *
- * The code has been made to work with highmem pages and will use a
- * destination page in its final resting place (if it happens
- * to allocate it). The end product of this is that most of the
- * physical address space, and most of RAM can be used.
- *
- * Future directions include:
- * - allocating a page table with the control code buffer identity
- * mapped, to simplify machine_kexec and make kexec_on_panic more
- * reliable.
- */
-
-/*
- * KIMAGE_NO_DEST is an impossible destination address..., for
- * allocating pages whose destination address we do not care about.
- */
-#define KIMAGE_NO_DEST (-1UL)
-
-static struct page *kimage_alloc_page(struct kimage *image,
- gfp_t gfp_mask,
- unsigned long dest);
-
-static int copy_user_segment_list(struct kimage *image,
- unsigned long nr_segments,
- struct kexec_segment __user *segments)
-{
- int ret;
- size_t segment_bytes;
-
- /* Read in the segments */
- image->nr_segments = nr_segments;
- segment_bytes = nr_segments * sizeof(*segments);
- ret = copy_from_user(image->segment, segments, segment_bytes);
- if (ret)
- ret = -EFAULT;
-
- return ret;
-}
-
-int sanity_check_segment_list(struct kimage *image)
-{
- int result, i;
- unsigned long nr_segments = image->nr_segments;
-
- /*
- * Verify we have good destination addresses. The caller is
- * responsible for making certain we don't attempt to load
- * the new image into invalid or reserved areas of RAM. This
- * just verifies it is an address we can use.
- *
- * Since the kernel does everything in page size chunks ensure
- * the destination addresses are page aligned. Too many
- * special cases crop of when we don't do this. The most
- * insidious is getting overlapping destination addresses
- * simply because addresses are changed to page size
- * granularity.
- */
- result = -EADDRNOTAVAIL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
- return result;
- if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
- return result;
- }
-
- /* Verify our destination addresses do not overlap.
- * If we alloed overlapping destination addresses
- * through very weird things can happen with no
- * easy explanation as one segment stops on another.
- */
- result = -EINVAL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
- unsigned long j;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- for (j = 0; j < i; j++) {
- unsigned long pstart, pend;
- pstart = image->segment[j].mem;
- pend = pstart + image->segment[j].memsz;
- /* Do the segments overlap ? */
- if ((mend > pstart) && (mstart < pend))
- return result;
- }
- }
-
- /* Ensure our buffer sizes are strictly less than
- * our memory sizes. This should always be the case,
- * and it is easier to check up front than to be surprised
- * later on.
- */
- result = -EINVAL;
- for (i = 0; i < nr_segments; i++) {
- if (image->segment[i].bufsz > image->segment[i].memsz)
- return result;
- }
-
- /*
- * Verify we have good destination addresses. Normally
- * the caller is responsible for making certain we don't
- * attempt to load the new image into invalid or reserved
- * areas of RAM. But crash kernels are preloaded into a
- * reserved area of ram. We must ensure the addresses
- * are in the reserved area otherwise preloading the
- * kernel could corrupt things.
- */
-
- if (image->type == KEXEC_TYPE_CRASH) {
- result = -EADDRNOTAVAIL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz - 1;
- /* Ensure we are within the crash kernel limits */
- if ((mstart < crashk_res.start) ||
- (mend > crashk_res.end))
- return result;
- }
- }
-
- return 0;
-}
-
-struct kimage *do_kimage_alloc_init(void)
-{
- struct kimage *image;
-
- /* Allocate a controlling structure */
- image = kzalloc(sizeof(*image), GFP_KERNEL);
- if (!image)
- return NULL;
-
- image->head = 0;
- image->entry = &image->head;
- image->last_entry = &image->head;
- image->control_page = ~0; /* By default this does not apply */
- image->type = KEXEC_TYPE_DEFAULT;
-
- /* Initialize the list of control pages */
- INIT_LIST_HEAD(&image->control_pages);
-
- /* Initialize the list of destination pages */
- INIT_LIST_HEAD(&image->dest_pages);
-
- /* Initialize the list of unusable pages */
- INIT_LIST_HEAD(&image->unusable_pages);
-
- return image;
-}
-
-static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
- unsigned long nr_segments,
- struct kexec_segment __user *segments,
- unsigned long flags)
-{
- int ret;
- struct kimage *image;
- bool kexec_on_panic = flags & KEXEC_ON_CRASH;
-
- if (kexec_on_panic) {
- /* Verify we have a valid entry point */
- if ((entry < crashk_res.start) || (entry > crashk_res.end))
- return -EADDRNOTAVAIL;
- }
-
- /* Allocate and initialize a controlling structure */
- image = do_kimage_alloc_init();
- if (!image)
- return -ENOMEM;
-
- image->start = entry;
-
- ret = copy_user_segment_list(image, nr_segments, segments);
- if (ret)
- goto out_free_image;
-
- ret = sanity_check_segment_list(image);
- if (ret)
- goto out_free_image;
-
- /* Enable the special crash kernel control page allocation policy. */
- if (kexec_on_panic) {
- image->control_page = crashk_res.start;
- image->type = KEXEC_TYPE_CRASH;
- }
-
- /*
- * Find a location for the control code buffer, and add it
- * the vector of segments so that it's pages will also be
- * counted as destination pages.
- */
- ret = -ENOMEM;
- image->control_code_page = kimage_alloc_control_pages(image,
- get_order(KEXEC_CONTROL_PAGE_SIZE));
- if (!image->control_code_page) {
- pr_err("Could not allocate control_code_buffer\n");
- goto out_free_image;
- }
-
- if (!kexec_on_panic) {
- image->swap_page = kimage_alloc_control_pages(image, 0);
- if (!image->swap_page) {
- pr_err("Could not allocate swap buffer\n");
- goto out_free_control_pages;
- }
- }
-
- *rimage = image;
- return 0;
-out_free_control_pages:
- kimage_free_page_list(&image->control_pages);
-out_free_image:
- kfree(image);
- return ret;
-}
-
-int kimage_is_destination_range(struct kimage *image,
- unsigned long start,
- unsigned long end)
-{
- unsigned long i;
-
- for (i = 0; i < image->nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((end > mstart) && (start < mend))
- return 1;
- }
-
- return 0;
-}
-
-static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
-{
- struct page *pages;
-
- pages = alloc_pages(gfp_mask, order);
- if (pages) {
- unsigned int count, i;
- pages->mapping = NULL;
- set_page_private(pages, order);
- count = 1 << order;
- for (i = 0; i < count; i++)
- SetPageReserved(pages + i);
- }
-
- return pages;
-}
-
-static void kimage_free_pages(struct page *page)
-{
- unsigned int order, count, i;
-
- order = page_private(page);
- count = 1 << order;
- for (i = 0; i < count; i++)
- ClearPageReserved(page + i);
- __free_pages(page, order);
-}
-
-void kimage_free_page_list(struct list_head *list)
-{
- struct list_head *pos, *next;
-
- list_for_each_safe(pos, next, list) {
- struct page *page;
-
- page = list_entry(pos, struct page, lru);
- list_del(&page->lru);
- kimage_free_pages(page);
- }
-}
-
-static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
- unsigned int order)
-{
- /* Control pages are special, they are the intermediaries
- * that are needed while we copy the rest of the pages
- * to their final resting place. As such they must
- * not conflict with either the destination addresses
- * or memory the kernel is already using.
- *
- * The only case where we really need more than one of
- * these are for architectures where we cannot disable
- * the MMU and must instead generate an identity mapped
- * page table for all of the memory.
- *
- * At worst this runs in O(N) of the image size.
- */
- struct list_head extra_pages;
- struct page *pages;
- unsigned int count;
-
- count = 1 << order;
- INIT_LIST_HEAD(&extra_pages);
-
- /* Loop while I can allocate a page and the page allocated
- * is a destination page.
- */
- do {
- unsigned long pfn, epfn, addr, eaddr;
-
- pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
- if (!pages)
- break;
- pfn = page_to_pfn(pages);
- epfn = pfn + count;
- addr = pfn << PAGE_SHIFT;
- eaddr = epfn << PAGE_SHIFT;
- if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
- kimage_is_destination_range(image, addr, eaddr)) {
- list_add(&pages->lru, &extra_pages);
- pages = NULL;
- }
- } while (!pages);
-
- if (pages) {
- /* Remember the allocated page... */
- list_add(&pages->lru, &image->control_pages);
-
- /* Because the page is already in it's destination
- * location we will never allocate another page at
- * that address. Therefore kimage_alloc_pages
- * will not return it (again) and we don't need
- * to give it an entry in image->segment[].
- */
- }
- /* Deal with the destination pages I have inadvertently allocated.
- *
- * Ideally I would convert multi-page allocations into single
- * page allocations, and add everything to image->dest_pages.
- *
- * For now it is simpler to just free the pages.
- */
- kimage_free_page_list(&extra_pages);
-
- return pages;
-}
-
-static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
- unsigned int order)
-{
- /* Control pages are special, they are the intermediaries
- * that are needed while we copy the rest of the pages
- * to their final resting place. As such they must
- * not conflict with either the destination addresses
- * or memory the kernel is already using.
- *
- * Control pages are also the only pags we must allocate
- * when loading a crash kernel. All of the other pages
- * are specified by the segments and we just memcpy
- * into them directly.
- *
- * The only case where we really need more than one of
- * these are for architectures where we cannot disable
- * the MMU and must instead generate an identity mapped
- * page table for all of the memory.
- *
- * Given the low demand this implements a very simple
- * allocator that finds the first hole of the appropriate
- * size in the reserved memory region, and allocates all
- * of the memory up to and including the hole.
- */
- unsigned long hole_start, hole_end, size;
- struct page *pages;
-
- pages = NULL;
- size = (1 << order) << PAGE_SHIFT;
- hole_start = (image->control_page + (size - 1)) & ~(size - 1);
- hole_end = hole_start + size - 1;
- while (hole_end <= crashk_res.end) {
- unsigned long i;
-
- if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT)
- break;
- /* See if I overlap any of the segments */
- for (i = 0; i < image->nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz - 1;
- if ((hole_end >= mstart) && (hole_start <= mend)) {
- /* Advance the hole to the end of the segment */
- hole_start = (mend + (size - 1)) & ~(size - 1);
- hole_end = hole_start + size - 1;
- break;
- }
- }
- /* If I don't overlap any segments I have found my hole! */
- if (i == image->nr_segments) {
- pages = pfn_to_page(hole_start >> PAGE_SHIFT);
- break;
- }
- }
- if (pages)
- image->control_page = hole_end;
-
- return pages;
-}
-
-
-struct page *kimage_alloc_control_pages(struct kimage *image,
- unsigned int order)
-{
- struct page *pages = NULL;
-
- switch (image->type) {
- case KEXEC_TYPE_DEFAULT:
- pages = kimage_alloc_normal_control_pages(image, order);
- break;
- case KEXEC_TYPE_CRASH:
- pages = kimage_alloc_crash_control_pages(image, order);
- break;
- }
-
- return pages;
-}
-
-static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
-{
- if (*image->entry != 0)
- image->entry++;
-
- if (image->entry == image->last_entry) {
- kimage_entry_t *ind_page;
- struct page *page;
-
- page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
- if (!page)
- return -ENOMEM;
-
- ind_page = page_address(page);
- *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
- image->entry = ind_page;
- image->last_entry = ind_page +
- ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
- }
- *image->entry = entry;
- image->entry++;
- *image->entry = 0;
-
- return 0;
-}
-
-static int kimage_set_destination(struct kimage *image,
- unsigned long destination)
-{
- int result;
-
- destination &= PAGE_MASK;
- result = kimage_add_entry(image, destination | IND_DESTINATION);
-
- return result;
-}
-
-
-static int kimage_add_page(struct kimage *image, unsigned long page)
-{
- int result;
-
- page &= PAGE_MASK;
- result = kimage_add_entry(image, page | IND_SOURCE);
-
- return result;
-}
-
-
-static void kimage_free_extra_pages(struct kimage *image)
-{
- /* Walk through and free any extra destination pages I may have */
- kimage_free_page_list(&image->dest_pages);
-
- /* Walk through and free any unusable pages I have cached */
- kimage_free_page_list(&image->unusable_pages);
-
-}
-void kimage_terminate(struct kimage *image)
-{
- if (*image->entry != 0)
- image->entry++;
-
- *image->entry = IND_DONE;
-}
-
-#define for_each_kimage_entry(image, ptr, entry) \
- for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
- ptr = (entry & IND_INDIRECTION) ? \
- phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
-
-static void kimage_free_entry(kimage_entry_t entry)
-{
- struct page *page;
-
- page = pfn_to_page(entry >> PAGE_SHIFT);
- kimage_free_pages(page);
-}
-
-void kimage_free(struct kimage *image)
-{
- kimage_entry_t *ptr, entry;
- kimage_entry_t ind = 0;
-
- if (!image)
- return;
-
- kimage_free_extra_pages(image);
- for_each_kimage_entry(image, ptr, entry) {
- if (entry & IND_INDIRECTION) {
- /* Free the previous indirection page */
- if (ind & IND_INDIRECTION)
- kimage_free_entry(ind);
- /* Save this indirection page until we are
- * done with it.
- */
- ind = entry;
- } else if (entry & IND_SOURCE)
- kimage_free_entry(entry);
- }
- /* Free the final indirection page */
- if (ind & IND_INDIRECTION)
- kimage_free_entry(ind);
-
- /* Handle any machine specific cleanup */
- machine_kexec_cleanup(image);
-
- /* Free the kexec control pages... */
- kimage_free_page_list(&image->control_pages);
-
- /*
- * Free up any temporary buffers allocated. This might hit if
- * error occurred much later after buffer allocation.
- */
- if (image->file_mode)
- kimage_file_post_load_cleanup(image);
-
- kfree(image);
-}
-
-static kimage_entry_t *kimage_dst_used(struct kimage *image,
- unsigned long page)
-{
- kimage_entry_t *ptr, entry;
- unsigned long destination = 0;
-
- for_each_kimage_entry(image, ptr, entry) {
- if (entry & IND_DESTINATION)
- destination = entry & PAGE_MASK;
- else if (entry & IND_SOURCE) {
- if (page == destination)
- return ptr;
- destination += PAGE_SIZE;
- }
- }
-
- return NULL;
-}
-
-static struct page *kimage_alloc_page(struct kimage *image,
- gfp_t gfp_mask,
- unsigned long destination)
-{
- /*
- * Here we implement safeguards to ensure that a source page
- * is not copied to its destination page before the data on
- * the destination page is no longer useful.
- *
- * To do this we maintain the invariant that a source page is
- * either its own destination page, or it is not a
- * destination page at all.
- *
- * That is slightly stronger than required, but the proof
- * that no problems will not occur is trivial, and the
- * implementation is simply to verify.
- *
- * When allocating all pages normally this algorithm will run
- * in O(N) time, but in the worst case it will run in O(N^2)
- * time. If the runtime is a problem the data structures can
- * be fixed.
- */
- struct page *page;
- unsigned long addr;
-
- /*
- * Walk through the list of destination pages, and see if I
- * have a match.
- */
- list_for_each_entry(page, &image->dest_pages, lru) {
- addr = page_to_pfn(page) << PAGE_SHIFT;
- if (addr == destination) {
- list_del(&page->lru);
- return page;
- }
- }
- page = NULL;
- while (1) {
- kimage_entry_t *old;
-
- /* Allocate a page, if we run out of memory give up */
- page = kimage_alloc_pages(gfp_mask, 0);
- if (!page)
- return NULL;
- /* If the page cannot be used file it away */
- if (page_to_pfn(page) >
- (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
- list_add(&page->lru, &image->unusable_pages);
- continue;
- }
- addr = page_to_pfn(page) << PAGE_SHIFT;
-
- /* If it is the destination page we want use it */
- if (addr == destination)
- break;
-
- /* If the page is not a destination page use it */
- if (!kimage_is_destination_range(image, addr,
- addr + PAGE_SIZE))
- break;
-
- /*
- * I know that the page is someones destination page.
- * See if there is already a source page for this
- * destination page. And if so swap the source pages.
- */
- old = kimage_dst_used(image, addr);
- if (old) {
- /* If so move it */
- unsigned long old_addr;
- struct page *old_page;
-
- old_addr = *old & PAGE_MASK;
- old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
- copy_highpage(page, old_page);
- *old = addr | (*old & ~PAGE_MASK);
-
- /* The old page I have found cannot be a
- * destination page, so return it if it's
- * gfp_flags honor the ones passed in.
- */
- if (!(gfp_mask & __GFP_HIGHMEM) &&
- PageHighMem(old_page)) {
- kimage_free_pages(old_page);
- continue;
- }
- addr = old_addr;
- page = old_page;
- break;
- } else {
- /* Place the page on the destination list I
- * will use it later.
- */
- list_add(&page->lru, &image->dest_pages);
- }
- }
-
- return page;
-}
-
-static int kimage_load_normal_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- unsigned long maddr;
- size_t ubytes, mbytes;
- int result;
- unsigned char __user *buf = NULL;
- unsigned char *kbuf = NULL;
-
- result = 0;
- if (image->file_mode)
- kbuf = segment->kbuf;
- else
- buf = segment->buf;
- ubytes = segment->bufsz;
- mbytes = segment->memsz;
- maddr = segment->mem;
-
- result = kimage_set_destination(image, maddr);
- if (result < 0)
- goto out;
-
- while (mbytes) {
- struct page *page;
- char *ptr;
- size_t uchunk, mchunk;
-
- page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
- if (!page) {
- result = -ENOMEM;
- goto out;
- }
- result = kimage_add_page(image, page_to_pfn(page)
- << PAGE_SHIFT);
- if (result < 0)
- goto out;
-
- ptr = kmap(page);
- /* Start with a clear page */
- clear_page(ptr);
- ptr += maddr & ~PAGE_MASK;
- mchunk = min_t(size_t, mbytes,
- PAGE_SIZE - (maddr & ~PAGE_MASK));
- uchunk = min(ubytes, mchunk);
-
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
- kunmap(page);
- if (result) {
- result = -EFAULT;
- goto out;
- }
- ubytes -= uchunk;
- maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
- mbytes -= mchunk;
- }
-out:
- return result;
-}
-
-static int kimage_load_crash_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- /* For crash dumps kernels we simply copy the data from
- * user space to it's destination.
- * We do things a page at a time for the sake of kmap.
- */
- unsigned long maddr;
- size_t ubytes, mbytes;
- int result;
- unsigned char __user *buf = NULL;
- unsigned char *kbuf = NULL;
-
- result = 0;
- if (image->file_mode)
- kbuf = segment->kbuf;
- else
- buf = segment->buf;
- ubytes = segment->bufsz;
- mbytes = segment->memsz;
- maddr = segment->mem;
- while (mbytes) {
- struct page *page;
- char *ptr;
- size_t uchunk, mchunk;
-
- page = pfn_to_page(maddr >> PAGE_SHIFT);
- if (!page) {
- result = -ENOMEM;
- goto out;
- }
- ptr = kmap(page);
- ptr += maddr & ~PAGE_MASK;
- mchunk = min_t(size_t, mbytes,
- PAGE_SIZE - (maddr & ~PAGE_MASK));
- uchunk = min(ubytes, mchunk);
- if (mchunk > uchunk) {
- /* Zero the trailing part of the page */
- memset(ptr + uchunk, 0, mchunk - uchunk);
- }
-
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
- kexec_flush_icache_page(page);
- kunmap(page);
- if (result) {
- result = -EFAULT;
- goto out;
- }
- ubytes -= uchunk;
- maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
- mbytes -= mchunk;
- }
-out:
- return result;
-}
-
-int kimage_load_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- int result = -ENOMEM;
-
- switch (image->type) {
- case KEXEC_TYPE_DEFAULT:
- result = kimage_load_normal_segment(image, segment);
- break;
- case KEXEC_TYPE_CRASH:
- result = kimage_load_crash_segment(image, segment);
- break;
- }
-
- return result;
-}
-
/*
* Exec Kernel system call: for obvious reasons only root may call it.
*
@@ -953,9 +35,6 @@ int kimage_load_segment(struct kimage *image,
* kexec does not sync, or unmount filesystems so if you need
* that to happen you need to do that yourself.
*/
-struct kimage *kexec_image;
-struct kimage *kexec_crash_image;
-int kexec_load_disabled;
SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
struct kexec_segment __user *, segments, unsigned long, flags)
@@ -1050,18 +129,6 @@ out:
return result;
}
-/*
- * Add and remove page tables for crashkernel memory
- *
- * Provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak crash_map_reserved_pages(void)
-{}
-
-void __weak crash_unmap_reserved_pages(void)
-{}
-
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
compat_ulong_t, nr_segments,
@@ -1100,646 +167,3 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
return sys_kexec_load(entry, nr_segments, ksegments, flags);
}
#endif
-
-void crash_kexec(struct pt_regs *regs)
-{
- /* Take the kexec_mutex 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 (mutex_trylock(&kexec_mutex)) {
- 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);
- }
- mutex_unlock(&kexec_mutex);
- }
-}
-
-size_t crash_get_memory_size(void)
-{
- size_t size = 0;
- mutex_lock(&kexec_mutex);
- if (crashk_res.end != crashk_res.start)
- size = resource_size(&crashk_res);
- mutex_unlock(&kexec_mutex);
- return size;
-}
-
-void __weak crash_free_reserved_phys_range(unsigned long begin,
- unsigned long end)
-{
- unsigned long addr;
-
- for (addr = begin; addr < end; addr += PAGE_SIZE)
- free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT));
-}
-
-int crash_shrink_memory(unsigned long new_size)
-{
- int ret = 0;
- unsigned long start, end;
- unsigned long old_size;
- struct resource *ram_res;
-
- mutex_lock(&kexec_mutex);
-
- if (kexec_crash_image) {
- ret = -ENOENT;
- goto unlock;
- }
- start = crashk_res.start;
- end = crashk_res.end;
- old_size = (end == 0) ? 0 : end - start + 1;
- if (new_size >= old_size) {
- ret = (new_size == old_size) ? 0 : -EINVAL;
- goto unlock;
- }
-
- ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
- if (!ram_res) {
- ret = -ENOMEM;
- goto unlock;
- }
-
- start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
- end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
-
- crash_map_reserved_pages();
- crash_free_reserved_phys_range(end, crashk_res.end);
-
- if ((start == end) && (crashk_res.parent != NULL))
- release_resource(&crashk_res);
-
- ram_res->start = end;
- ram_res->end = crashk_res.end;
- ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
- ram_res->name = "System RAM";
-
- crashk_res.end = end - 1;
-
- insert_resource(&iomem_resource, ram_res);
- crash_unmap_reserved_pages();
-
-unlock:
- mutex_unlock(&kexec_mutex);
- return ret;
-}
-
-static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
- size_t data_len)
-{
- struct elf_note note;
-
- note.n_namesz = strlen(name) + 1;
- note.n_descsz = data_len;
- note.n_type = type;
- memcpy(buf, ¬e, sizeof(note));
- buf += (sizeof(note) + 3)/4;
- memcpy(buf, name, note.n_namesz);
- buf += (note.n_namesz + 3)/4;
- memcpy(buf, data, note.n_descsz);
- buf += (note.n_descsz + 3)/4;
-
- return buf;
-}
-
-static void final_note(u32 *buf)
-{
- struct elf_note note;
-
- note.n_namesz = 0;
- note.n_descsz = 0;
- note.n_type = 0;
- memcpy(buf, ¬e, sizeof(note));
-}
-
-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.pr_pid = current->pid;
- elf_core_copy_kernel_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. */
- crash_notes = alloc_percpu(note_buf_t);
- if (!crash_notes) {
- pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
- return -ENOMEM;
- }
- return 0;
-}
-subsys_initcall(crash_notes_memory_init);
-
-
-/*
- * 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;
-
- /* 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 >= system_ram) {
- pr_warn("crashkernel: invalid size\n");
- return -EINVAL;
- }
-
- /* match ? */
- if (system_ram >= start && system_ram < 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;
- }
- }
- }
-
- 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\n");
- 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\n");
- return -EINVAL;
- }
- cur += strlen(suffix);
- if (*cur != ' ' && *cur != '\0') {
- pr_warn("crashkernel: unrecognized char\n");
- 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);
- }
-
- if (!ck_cmdline)
- return NULL;
-
- 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 *name,
- const char *suffix)
-{
- char *first_colon, *first_space;
- char *ck_cmdline;
-
- BUG_ON(!crash_size || !crash_base);
- *crash_size = 0;
- *crash_base = 0;
-
- ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
-
- if (!ck_cmdline)
- return -EINVAL;
-
- 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.
- */
-int __init parse_crashkernel(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", NULL);
-}
-
-int __init parse_crashkernel_high(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", suffix_tbl[SUFFIX_HIGH]);
-}
-
-int __init parse_crashkernel_low(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", suffix_tbl[SUFFIX_LOW]);
-}
-
-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_save_vmcoreinfo(void)
-{
- vmcoreinfo_append_str("CRASHTIME=%ld\n", get_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, vmcoreinfo_max_size - vmcoreinfo_size);
-
- memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
-
- vmcoreinfo_size += r;
-}
-
-/*
- * provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak arch_crash_save_vmcoreinfo(void)
-{}
-
-unsigned long __weak paddr_vmcoreinfo_note(void)
-{
- return __pa((unsigned long)(char *)&vmcoreinfo_note);
-}
-
-static int __init crash_save_vmcoreinfo_init(void)
-{
- VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
- VMCOREINFO_PAGESIZE(PAGE_SIZE);
-
- VMCOREINFO_SYMBOL(init_uts_ns);
- VMCOREINFO_SYMBOL(node_online_map);
-#ifdef CONFIG_MMU
- VMCOREINFO_SYMBOL(swapper_pg_dir);
-#endif
- VMCOREINFO_SYMBOL(_stext);
- VMCOREINFO_SYMBOL(vmap_area_list);
-
-#ifndef CONFIG_NEED_MULTIPLE_NODES
- VMCOREINFO_SYMBOL(mem_map);
- VMCOREINFO_SYMBOL(contig_page_data);
-#endif
-#ifdef CONFIG_SPARSEMEM
- VMCOREINFO_SYMBOL(mem_section);
- VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
- VMCOREINFO_STRUCT_SIZE(mem_section);
- VMCOREINFO_OFFSET(mem_section, section_mem_map);
-#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, _count);
- VMCOREINFO_OFFSET(page, mapping);
- VMCOREINFO_OFFSET(page, lru);
- VMCOREINFO_OFFSET(page, _mapcount);
- VMCOREINFO_OFFSET(page, private);
- VMCOREINFO_OFFSET(pglist_data, node_zones);
- VMCOREINFO_OFFSET(pglist_data, nr_zones);
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
- 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_OFFSET(vmap_area, va_start);
- VMCOREINFO_OFFSET(vmap_area, list);
- VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
- log_buf_kexec_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_slab);
-#ifdef CONFIG_MEMORY_FAILURE
- VMCOREINFO_NUMBER(PG_hwpoison);
-#endif
- VMCOREINFO_NUMBER(PG_head_mask);
- VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
-#ifdef CONFIG_HUGETLBFS
- VMCOREINFO_SYMBOL(free_huge_page);
-#endif
-
- arch_crash_save_vmcoreinfo();
- update_vmcoreinfo_note();
-
- return 0;
-}
-
-subsys_initcall(crash_save_vmcoreinfo_init);
-
-/*
- * Move into place and start executing a preloaded standalone
- * executable. If nothing was preloaded return an error.
- */
-int kernel_kexec(void)
-{
- int error = 0;
-
- if (!mutex_trylock(&kexec_mutex))
- return -EBUSY;
- if (!kexec_image) {
- error = -EINVAL;
- goto Unlock;
- }
-
-#ifdef CONFIG_KEXEC_JUMP
- if (kexec_image->preserve_context) {
- lock_system_sleep();
- pm_prepare_console();
- error = freeze_processes();
- if (error) {
- error = -EBUSY;
- goto Restore_console;
- }
- suspend_console();
- error = dpm_suspend_start(PMSG_FREEZE);
- if (error)
- goto Resume_console;
- /* At this point, dpm_suspend_start() has been called,
- * but *not* dpm_suspend_end(). We *must* call
- * dpm_suspend_end() now. Otherwise, drivers for
- * some devices (e.g. interrupt controllers) become
- * desynchronized with the actual state of the
- * hardware at resume time, and evil weirdness ensues.
- */
- error = dpm_suspend_end(PMSG_FREEZE);
- if (error)
- goto Resume_devices;
- error = disable_nonboot_cpus();
- if (error)
- goto Enable_cpus;
- local_irq_disable();
- error = syscore_suspend();
- if (error)
- goto Enable_irqs;
- } else
-#endif
- {
- kexec_in_progress = true;
- kernel_restart_prepare(NULL);
- migrate_to_reboot_cpu();
-
- /*
- * migrate_to_reboot_cpu() disables CPU hotplug assuming that
- * no further code needs to use CPU hotplug (which is true in
- * the reboot case). However, the kexec path depends on using
- * CPU hotplug again; so re-enable it here.
- */
- cpu_hotplug_enable();
- pr_emerg("Starting new kernel\n");
- machine_shutdown();
- }
-
- machine_kexec(kexec_image);
-
-#ifdef CONFIG_KEXEC_JUMP
- if (kexec_image->preserve_context) {
- syscore_resume();
- Enable_irqs:
- local_irq_enable();
- Enable_cpus:
- enable_nonboot_cpus();
- dpm_resume_start(PMSG_RESTORE);
- Resume_devices:
- dpm_resume_end(PMSG_RESTORE);
- Resume_console:
- resume_console();
- thaw_processes();
- Restore_console:
- pm_restore_console();
- unlock_system_sleep();
- }
-#endif
-
- Unlock:
- mutex_unlock(&kexec_mutex);
- return error;
-}
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
new file mode 100644
index 0000000..8d4c047
--- /dev/null
+++ b/kernel/kexec_core.c
@@ -0,0 +1,1594 @@
+/*
+ * kexec.c - kexec system call core code.
+ * Copyright (C) 2002-2004 Eric Biederman <[email protected]>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#define pr_fmt(fmt) "kexec: " fmt
+
+#include <linux/capability.h>
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/kexec.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/highmem.h>
+#include <linux/syscalls.h>
+#include <linux/reboot.h>
+#include <linux/ioport.h>
+#include <linux/hardirq.h>
+#include <linux/elf.h>
+#include <linux/elfcore.h>
+#include <linux/utsname.h>
+#include <linux/numa.h>
+#include <linux/suspend.h>
+#include <linux/device.h>
+#include <linux/freezer.h>
+#include <linux/pm.h>
+#include <linux/cpu.h>
+#include <linux/console.h>
+#include <linux/vmalloc.h>
+#include <linux/swap.h>
+#include <linux/syscore_ops.h>
+#include <linux/compiler.h>
+#include <linux/hugetlb.h>
+
+#include <asm/page.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/sections.h>
+
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include "kexec_internal.h"
+
+DEFINE_MUTEX(kexec_mutex);
+
+/* Per cpu memory for storing cpu states in case of system crash. */
+note_buf_t __percpu *crash_notes;
+
+/* vmcoreinfo stuff */
+static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
+u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
+size_t vmcoreinfo_size;
+size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
+
+/* Flag to indicate we are going to kexec a new kernel */
+bool kexec_in_progress = false;
+
+
+/* Location of the reserved area for the crash kernel */
+struct resource crashk_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
+struct resource crashk_low_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
+
+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 do_exit() 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;
+}
+
+/*
+ * When kexec transitions to the new kernel there is a one-to-one
+ * mapping between physical and virtual addresses. On processors
+ * where you can disable the MMU this is trivial, and easy. For
+ * others it is still a simple predictable page table to setup.
+ *
+ * In that environment kexec copies the new kernel to its final
+ * resting place. This means I can only support memory whose
+ * physical address can fit in an unsigned long. In particular
+ * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled.
+ * If the assembly stub has more restrictive requirements
+ * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be
+ * defined more restrictively in <asm/kexec.h>.
+ *
+ * The code for the transition from the current kernel to the
+ * the new kernel is placed in the control_code_buffer, whose size
+ * is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single
+ * page of memory is necessary, but some architectures require more.
+ * Because this memory must be identity mapped in the transition from
+ * virtual to physical addresses it must live in the range
+ * 0 - TASK_SIZE, as only the user space mappings are arbitrarily
+ * modifiable.
+ *
+ * The assembly stub in the control code buffer is passed a linked list
+ * of descriptor pages detailing the source pages of the new kernel,
+ * and the destination addresses of those source pages. As this data
+ * structure is not used in the context of the current OS, it must
+ * be self-contained.
+ *
+ * The code has been made to work with highmem pages and will use a
+ * destination page in its final resting place (if it happens
+ * to allocate it). The end product of this is that most of the
+ * physical address space, and most of RAM can be used.
+ *
+ * Future directions include:
+ * - allocating a page table with the control code buffer identity
+ * mapped, to simplify machine_kexec and make kexec_on_panic more
+ * reliable.
+ */
+
+/*
+ * KIMAGE_NO_DEST is an impossible destination address..., for
+ * allocating pages whose destination address we do not care about.
+ */
+#define KIMAGE_NO_DEST (-1UL)
+
+static struct page *kimage_alloc_page(struct kimage *image,
+ gfp_t gfp_mask,
+ unsigned long dest);
+
+static int copy_user_segment_list(struct kimage *image,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments)
+{
+ int ret;
+ size_t segment_bytes;
+
+ /* Read in the segments */
+ image->nr_segments = nr_segments;
+ segment_bytes = nr_segments * sizeof(*segments);
+ ret = copy_from_user(image->segment, segments, segment_bytes);
+ if (ret)
+ ret = -EFAULT;
+
+ return ret;
+}
+
+int sanity_check_segment_list(struct kimage *image)
+{
+ int result, i;
+ unsigned long nr_segments = image->nr_segments;
+
+ /*
+ * Verify we have good destination addresses. The caller is
+ * responsible for making certain we don't attempt to load
+ * the new image into invalid or reserved areas of RAM. This
+ * just verifies it is an address we can use.
+ *
+ * Since the kernel does everything in page size chunks ensure
+ * the destination addresses are page aligned. Too many
+ * special cases crop of when we don't do this. The most
+ * insidious is getting overlapping destination addresses
+ * simply because addresses are changed to page size
+ * granularity.
+ */
+ result = -EADDRNOTAVAIL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
+ return result;
+ if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
+ return result;
+ }
+
+ /* Verify our destination addresses do not overlap.
+ * If we alloed overlapping destination addresses
+ * through very weird things can happen with no
+ * easy explanation as one segment stops on another.
+ */
+ result = -EINVAL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+ unsigned long j;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ for (j = 0; j < i; j++) {
+ unsigned long pstart, pend;
+ pstart = image->segment[j].mem;
+ pend = pstart + image->segment[j].memsz;
+ /* Do the segments overlap ? */
+ if ((mend > pstart) && (mstart < pend))
+ return result;
+ }
+ }
+
+ /* Ensure our buffer sizes are strictly less than
+ * our memory sizes. This should always be the case,
+ * and it is easier to check up front than to be surprised
+ * later on.
+ */
+ result = -EINVAL;
+ for (i = 0; i < nr_segments; i++) {
+ if (image->segment[i].bufsz > image->segment[i].memsz)
+ return result;
+ }
+
+ /*
+ * Verify we have good destination addresses. Normally
+ * the caller is responsible for making certain we don't
+ * attempt to load the new image into invalid or reserved
+ * areas of RAM. But crash kernels are preloaded into a
+ * reserved area of ram. We must ensure the addresses
+ * are in the reserved area otherwise preloading the
+ * kernel could corrupt things.
+ */
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ result = -EADDRNOTAVAIL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz - 1;
+ /* Ensure we are within the crash kernel limits */
+ if ((mstart < crashk_res.start) ||
+ (mend > crashk_res.end))
+ return result;
+ }
+ }
+
+ return 0;
+}
+
+struct kimage *do_kimage_alloc_init(void)
+{
+ struct kimage *image;
+
+ /* Allocate a controlling structure */
+ image = kzalloc(sizeof(*image), GFP_KERNEL);
+ if (!image)
+ return NULL;
+
+ image->head = 0;
+ image->entry = &image->head;
+ image->last_entry = &image->head;
+ image->control_page = ~0; /* By default this does not apply */
+ image->type = KEXEC_TYPE_DEFAULT;
+
+ /* Initialize the list of control pages */
+ INIT_LIST_HEAD(&image->control_pages);
+
+ /* Initialize the list of destination pages */
+ INIT_LIST_HEAD(&image->dest_pages);
+
+ /* Initialize the list of unusable pages */
+ INIT_LIST_HEAD(&image->unusable_pages);
+
+ return image;
+}
+
+int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments,
+ unsigned long flags)
+{
+ int ret;
+ struct kimage *image;
+ bool kexec_on_panic = flags & KEXEC_ON_CRASH;
+
+ if (kexec_on_panic) {
+ /* Verify we have a valid entry point */
+ if ((entry < crashk_res.start) || (entry > crashk_res.end))
+ return -EADDRNOTAVAIL;
+ }
+
+ /* Allocate and initialize a controlling structure */
+ image = do_kimage_alloc_init();
+ if (!image)
+ return -ENOMEM;
+
+ image->start = entry;
+
+ ret = copy_user_segment_list(image, nr_segments, segments);
+ if (ret)
+ goto out_free_image;
+
+ ret = sanity_check_segment_list(image);
+ if (ret)
+ goto out_free_image;
+
+ /* Enable the special crash kernel control page allocation policy. */
+ if (kexec_on_panic) {
+ image->control_page = crashk_res.start;
+ image->type = KEXEC_TYPE_CRASH;
+ }
+
+ /*
+ * Find a location for the control code buffer, and add it
+ * the vector of segments so that it's pages will also be
+ * counted as destination pages.
+ */
+ ret = -ENOMEM;
+ image->control_code_page = kimage_alloc_control_pages(image,
+ get_order(KEXEC_CONTROL_PAGE_SIZE));
+ if (!image->control_code_page) {
+ pr_err("Could not allocate control_code_buffer\n");
+ goto out_free_image;
+ }
+
+ if (!kexec_on_panic) {
+ image->swap_page = kimage_alloc_control_pages(image, 0);
+ if (!image->swap_page) {
+ pr_err("Could not allocate swap buffer\n");
+ goto out_free_control_pages;
+ }
+ }
+
+ *rimage = image;
+ return 0;
+out_free_control_pages:
+ kimage_free_page_list(&image->control_pages);
+out_free_image:
+ kfree(image);
+ return ret;
+}
+
+int kimage_is_destination_range(struct kimage *image,
+ unsigned long start,
+ unsigned long end)
+{
+ unsigned long i;
+
+ for (i = 0; i < image->nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ if ((end > mstart) && (start < mend))
+ return 1;
+ }
+
+ return 0;
+}
+
+static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
+{
+ struct page *pages;
+
+ pages = alloc_pages(gfp_mask, order);
+ if (pages) {
+ unsigned int count, i;
+ pages->mapping = NULL;
+ set_page_private(pages, order);
+ count = 1 << order;
+ for (i = 0; i < count; i++)
+ SetPageReserved(pages + i);
+ }
+
+ return pages;
+}
+
+static void kimage_free_pages(struct page *page)
+{
+ unsigned int order, count, i;
+
+ order = page_private(page);
+ count = 1 << order;
+ for (i = 0; i < count; i++)
+ ClearPageReserved(page + i);
+ __free_pages(page, order);
+}
+
+void kimage_free_page_list(struct list_head *list)
+{
+ struct list_head *pos, *next;
+
+ list_for_each_safe(pos, next, list) {
+ struct page *page;
+
+ page = list_entry(pos, struct page, lru);
+ list_del(&page->lru);
+ kimage_free_pages(page);
+ }
+}
+
+static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ /* Control pages are special, they are the intermediaries
+ * that are needed while we copy the rest of the pages
+ * to their final resting place. As such they must
+ * not conflict with either the destination addresses
+ * or memory the kernel is already using.
+ *
+ * The only case where we really need more than one of
+ * these are for architectures where we cannot disable
+ * the MMU and must instead generate an identity mapped
+ * page table for all of the memory.
+ *
+ * At worst this runs in O(N) of the image size.
+ */
+ struct list_head extra_pages;
+ struct page *pages;
+ unsigned int count;
+
+ count = 1 << order;
+ INIT_LIST_HEAD(&extra_pages);
+
+ /* Loop while I can allocate a page and the page allocated
+ * is a destination page.
+ */
+ do {
+ unsigned long pfn, epfn, addr, eaddr;
+
+ pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
+ if (!pages)
+ break;
+ pfn = page_to_pfn(pages);
+ epfn = pfn + count;
+ addr = pfn << PAGE_SHIFT;
+ eaddr = epfn << PAGE_SHIFT;
+ if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
+ kimage_is_destination_range(image, addr, eaddr)) {
+ list_add(&pages->lru, &extra_pages);
+ pages = NULL;
+ }
+ } while (!pages);
+
+ if (pages) {
+ /* Remember the allocated page... */
+ list_add(&pages->lru, &image->control_pages);
+
+ /* Because the page is already in it's destination
+ * location we will never allocate another page at
+ * that address. Therefore kimage_alloc_pages
+ * will not return it (again) and we don't need
+ * to give it an entry in image->segment[].
+ */
+ }
+ /* Deal with the destination pages I have inadvertently allocated.
+ *
+ * Ideally I would convert multi-page allocations into single
+ * page allocations, and add everything to image->dest_pages.
+ *
+ * For now it is simpler to just free the pages.
+ */
+ kimage_free_page_list(&extra_pages);
+
+ return pages;
+}
+
+static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ /* Control pages are special, they are the intermediaries
+ * that are needed while we copy the rest of the pages
+ * to their final resting place. As such they must
+ * not conflict with either the destination addresses
+ * or memory the kernel is already using.
+ *
+ * Control pages are also the only pags we must allocate
+ * when loading a crash kernel. All of the other pages
+ * are specified by the segments and we just memcpy
+ * into them directly.
+ *
+ * The only case where we really need more than one of
+ * these are for architectures where we cannot disable
+ * the MMU and must instead generate an identity mapped
+ * page table for all of the memory.
+ *
+ * Given the low demand this implements a very simple
+ * allocator that finds the first hole of the appropriate
+ * size in the reserved memory region, and allocates all
+ * of the memory up to and including the hole.
+ */
+ unsigned long hole_start, hole_end, size;
+ struct page *pages;
+
+ pages = NULL;
+ size = (1 << order) << PAGE_SHIFT;
+ hole_start = (image->control_page + (size - 1)) & ~(size - 1);
+ hole_end = hole_start + size - 1;
+ while (hole_end <= crashk_res.end) {
+ unsigned long i;
+
+ if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT)
+ break;
+ /* See if I overlap any of the segments */
+ for (i = 0; i < image->nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz - 1;
+ if ((hole_end >= mstart) && (hole_start <= mend)) {
+ /* Advance the hole to the end of the segment */
+ hole_start = (mend + (size - 1)) & ~(size - 1);
+ hole_end = hole_start + size - 1;
+ break;
+ }
+ }
+ /* If I don't overlap any segments I have found my hole! */
+ if (i == image->nr_segments) {
+ pages = pfn_to_page(hole_start >> PAGE_SHIFT);
+ break;
+ }
+ }
+ if (pages)
+ image->control_page = hole_end;
+
+ return pages;
+}
+
+
+struct page *kimage_alloc_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ struct page *pages = NULL;
+
+ switch (image->type) {
+ case KEXEC_TYPE_DEFAULT:
+ pages = kimage_alloc_normal_control_pages(image, order);
+ break;
+ case KEXEC_TYPE_CRASH:
+ pages = kimage_alloc_crash_control_pages(image, order);
+ break;
+ }
+
+ return pages;
+}
+
+static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
+{
+ if (*image->entry != 0)
+ image->entry++;
+
+ if (image->entry == image->last_entry) {
+ kimage_entry_t *ind_page;
+ struct page *page;
+
+ page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
+ if (!page)
+ return -ENOMEM;
+
+ ind_page = page_address(page);
+ *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
+ image->entry = ind_page;
+ image->last_entry = ind_page +
+ ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
+ }
+ *image->entry = entry;
+ image->entry++;
+ *image->entry = 0;
+
+ return 0;
+}
+
+static int kimage_set_destination(struct kimage *image,
+ unsigned long destination)
+{
+ int result;
+
+ destination &= PAGE_MASK;
+ result = kimage_add_entry(image, destination | IND_DESTINATION);
+
+ return result;
+}
+
+
+static int kimage_add_page(struct kimage *image, unsigned long page)
+{
+ int result;
+
+ page &= PAGE_MASK;
+ result = kimage_add_entry(image, page | IND_SOURCE);
+
+ return result;
+}
+
+
+static void kimage_free_extra_pages(struct kimage *image)
+{
+ /* Walk through and free any extra destination pages I may have */
+ kimage_free_page_list(&image->dest_pages);
+
+ /* Walk through and free any unusable pages I have cached */
+ kimage_free_page_list(&image->unusable_pages);
+
+}
+void kimage_terminate(struct kimage *image)
+{
+ if (*image->entry != 0)
+ image->entry++;
+
+ *image->entry = IND_DONE;
+}
+
+#define for_each_kimage_entry(image, ptr, entry) \
+ for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
+ ptr = (entry & IND_INDIRECTION) ? \
+ phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
+
+static void kimage_free_entry(kimage_entry_t entry)
+{
+ struct page *page;
+
+ page = pfn_to_page(entry >> PAGE_SHIFT);
+ kimage_free_pages(page);
+}
+
+void kimage_free(struct kimage *image)
+{
+ kimage_entry_t *ptr, entry;
+ kimage_entry_t ind = 0;
+
+ if (!image)
+ return;
+
+ kimage_free_extra_pages(image);
+ for_each_kimage_entry(image, ptr, entry) {
+ if (entry & IND_INDIRECTION) {
+ /* Free the previous indirection page */
+ if (ind & IND_INDIRECTION)
+ kimage_free_entry(ind);
+ /* Save this indirection page until we are
+ * done with it.
+ */
+ ind = entry;
+ } else if (entry & IND_SOURCE)
+ kimage_free_entry(entry);
+ }
+ /* Free the final indirection page */
+ if (ind & IND_INDIRECTION)
+ kimage_free_entry(ind);
+
+ /* Handle any machine specific cleanup */
+ machine_kexec_cleanup(image);
+
+ /* Free the kexec control pages... */
+ kimage_free_page_list(&image->control_pages);
+
+ /*
+ * Free up any temporary buffers allocated. This might hit if
+ * error occurred much later after buffer allocation.
+ */
+ if (image->file_mode)
+ kimage_file_post_load_cleanup(image);
+
+ kfree(image);
+}
+
+static kimage_entry_t *kimage_dst_used(struct kimage *image,
+ unsigned long page)
+{
+ kimage_entry_t *ptr, entry;
+ unsigned long destination = 0;
+
+ for_each_kimage_entry(image, ptr, entry) {
+ if (entry & IND_DESTINATION)
+ destination = entry & PAGE_MASK;
+ else if (entry & IND_SOURCE) {
+ if (page == destination)
+ return ptr;
+ destination += PAGE_SIZE;
+ }
+ }
+
+ return NULL;
+}
+
+static struct page *kimage_alloc_page(struct kimage *image,
+ gfp_t gfp_mask,
+ unsigned long destination)
+{
+ /*
+ * Here we implement safeguards to ensure that a source page
+ * is not copied to its destination page before the data on
+ * the destination page is no longer useful.
+ *
+ * To do this we maintain the invariant that a source page is
+ * either its own destination page, or it is not a
+ * destination page at all.
+ *
+ * That is slightly stronger than required, but the proof
+ * that no problems will not occur is trivial, and the
+ * implementation is simply to verify.
+ *
+ * When allocating all pages normally this algorithm will run
+ * in O(N) time, but in the worst case it will run in O(N^2)
+ * time. If the runtime is a problem the data structures can
+ * be fixed.
+ */
+ struct page *page;
+ unsigned long addr;
+
+ /*
+ * Walk through the list of destination pages, and see if I
+ * have a match.
+ */
+ list_for_each_entry(page, &image->dest_pages, lru) {
+ addr = page_to_pfn(page) << PAGE_SHIFT;
+ if (addr == destination) {
+ list_del(&page->lru);
+ return page;
+ }
+ }
+ page = NULL;
+ while (1) {
+ kimage_entry_t *old;
+
+ /* Allocate a page, if we run out of memory give up */
+ page = kimage_alloc_pages(gfp_mask, 0);
+ if (!page)
+ return NULL;
+ /* If the page cannot be used file it away */
+ if (page_to_pfn(page) >
+ (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
+ list_add(&page->lru, &image->unusable_pages);
+ continue;
+ }
+ addr = page_to_pfn(page) << PAGE_SHIFT;
+
+ /* If it is the destination page we want use it */
+ if (addr == destination)
+ break;
+
+ /* If the page is not a destination page use it */
+ if (!kimage_is_destination_range(image, addr,
+ addr + PAGE_SIZE))
+ break;
+
+ /*
+ * I know that the page is someones destination page.
+ * See if there is already a source page for this
+ * destination page. And if so swap the source pages.
+ */
+ old = kimage_dst_used(image, addr);
+ if (old) {
+ /* If so move it */
+ unsigned long old_addr;
+ struct page *old_page;
+
+ old_addr = *old & PAGE_MASK;
+ old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
+ copy_highpage(page, old_page);
+ *old = addr | (*old & ~PAGE_MASK);
+
+ /* The old page I have found cannot be a
+ * destination page, so return it if it's
+ * gfp_flags honor the ones passed in.
+ */
+ if (!(gfp_mask & __GFP_HIGHMEM) &&
+ PageHighMem(old_page)) {
+ kimage_free_pages(old_page);
+ continue;
+ }
+ addr = old_addr;
+ page = old_page;
+ break;
+ } else {
+ /* Place the page on the destination list I
+ * will use it later.
+ */
+ list_add(&page->lru, &image->dest_pages);
+ }
+ }
+
+ return page;
+}
+
+static int kimage_load_normal_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ unsigned long maddr;
+ size_t ubytes, mbytes;
+ int result;
+ unsigned char __user *buf = NULL;
+ unsigned char *kbuf = NULL;
+
+ result = 0;
+ if (image->file_mode)
+ kbuf = segment->kbuf;
+ else
+ buf = segment->buf;
+ ubytes = segment->bufsz;
+ mbytes = segment->memsz;
+ maddr = segment->mem;
+
+ result = kimage_set_destination(image, maddr);
+ if (result < 0)
+ goto out;
+
+ while (mbytes) {
+ struct page *page;
+ char *ptr;
+ size_t uchunk, mchunk;
+
+ page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ result = kimage_add_page(image, page_to_pfn(page)
+ << PAGE_SHIFT);
+ if (result < 0)
+ goto out;
+
+ ptr = kmap(page);
+ /* Start with a clear page */
+ clear_page(ptr);
+ ptr += maddr & ~PAGE_MASK;
+ mchunk = min_t(size_t, mbytes,
+ PAGE_SIZE - (maddr & ~PAGE_MASK));
+ uchunk = min(ubytes, mchunk);
+
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ kunmap(page);
+ if (result) {
+ result = -EFAULT;
+ goto out;
+ }
+ ubytes -= uchunk;
+ maddr += mchunk;
+ if (image->file_mode)
+ kbuf += mchunk;
+ else
+ buf += mchunk;
+ mbytes -= mchunk;
+ }
+out:
+ return result;
+}
+
+static int kimage_load_crash_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ /* For crash dumps kernels we simply copy the data from
+ * user space to it's destination.
+ * We do things a page at a time for the sake of kmap.
+ */
+ unsigned long maddr;
+ size_t ubytes, mbytes;
+ int result;
+ unsigned char __user *buf = NULL;
+ unsigned char *kbuf = NULL;
+
+ result = 0;
+ if (image->file_mode)
+ kbuf = segment->kbuf;
+ else
+ buf = segment->buf;
+ ubytes = segment->bufsz;
+ mbytes = segment->memsz;
+ maddr = segment->mem;
+ while (mbytes) {
+ struct page *page;
+ char *ptr;
+ size_t uchunk, mchunk;
+
+ page = pfn_to_page(maddr >> PAGE_SHIFT);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ ptr = kmap(page);
+ ptr += maddr & ~PAGE_MASK;
+ mchunk = min_t(size_t, mbytes,
+ PAGE_SIZE - (maddr & ~PAGE_MASK));
+ uchunk = min(ubytes, mchunk);
+ if (mchunk > uchunk) {
+ /* Zero the trailing part of the page */
+ memset(ptr + uchunk, 0, mchunk - uchunk);
+ }
+
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ kexec_flush_icache_page(page);
+ kunmap(page);
+ if (result) {
+ result = -EFAULT;
+ goto out;
+ }
+ ubytes -= uchunk;
+ maddr += mchunk;
+ if (image->file_mode)
+ kbuf += mchunk;
+ else
+ buf += mchunk;
+ mbytes -= mchunk;
+ }
+out:
+ return result;
+}
+
+int kimage_load_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ int result = -ENOMEM;
+
+ switch (image->type) {
+ case KEXEC_TYPE_DEFAULT:
+ result = kimage_load_normal_segment(image, segment);
+ break;
+ case KEXEC_TYPE_CRASH:
+ result = kimage_load_crash_segment(image, segment);
+ break;
+ }
+
+ return result;
+}
+
+struct kimage *kexec_image;
+struct kimage *kexec_crash_image;
+int kexec_load_disabled;
+
+void crash_kexec(struct pt_regs *regs)
+{
+ /* Take the kexec_mutex 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 (mutex_trylock(&kexec_mutex)) {
+ 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);
+ }
+ mutex_unlock(&kexec_mutex);
+ }
+}
+
+size_t crash_get_memory_size(void)
+{
+ size_t size = 0;
+ mutex_lock(&kexec_mutex);
+ if (crashk_res.end != crashk_res.start)
+ size = resource_size(&crashk_res);
+ mutex_unlock(&kexec_mutex);
+ return size;
+}
+
+void __weak crash_free_reserved_phys_range(unsigned long begin,
+ unsigned long end)
+{
+ unsigned long addr;
+
+ for (addr = begin; addr < end; addr += PAGE_SIZE)
+ free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT));
+}
+
+int crash_shrink_memory(unsigned long new_size)
+{
+ int ret = 0;
+ unsigned long start, end;
+ unsigned long old_size;
+ struct resource *ram_res;
+
+ mutex_lock(&kexec_mutex);
+
+ if (kexec_crash_image) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+ start = crashk_res.start;
+ end = crashk_res.end;
+ old_size = (end == 0) ? 0 : end - start + 1;
+ if (new_size >= old_size) {
+ ret = (new_size == old_size) ? 0 : -EINVAL;
+ goto unlock;
+ }
+
+ ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
+ if (!ram_res) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
+ end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
+
+ crash_map_reserved_pages();
+ crash_free_reserved_phys_range(end, crashk_res.end);
+
+ if ((start == end) && (crashk_res.parent != NULL))
+ release_resource(&crashk_res);
+
+ ram_res->start = end;
+ ram_res->end = crashk_res.end;
+ ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
+ ram_res->name = "System RAM";
+
+ crashk_res.end = end - 1;
+
+ insert_resource(&iomem_resource, ram_res);
+ crash_unmap_reserved_pages();
+
+unlock:
+ mutex_unlock(&kexec_mutex);
+ return ret;
+}
+
+static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
+ size_t data_len)
+{
+ struct elf_note note;
+
+ note.n_namesz = strlen(name) + 1;
+ note.n_descsz = data_len;
+ note.n_type = type;
+ memcpy(buf, ¬e, sizeof(note));
+ buf += (sizeof(note) + 3)/4;
+ memcpy(buf, name, note.n_namesz);
+ buf += (note.n_namesz + 3)/4;
+ memcpy(buf, data, note.n_descsz);
+ buf += (note.n_descsz + 3)/4;
+
+ return buf;
+}
+
+static void final_note(u32 *buf)
+{
+ struct elf_note note;
+
+ note.n_namesz = 0;
+ note.n_descsz = 0;
+ note.n_type = 0;
+ memcpy(buf, ¬e, sizeof(note));
+}
+
+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.pr_pid = current->pid;
+ elf_core_copy_kernel_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. */
+ crash_notes = alloc_percpu(note_buf_t);
+ if (!crash_notes) {
+ pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
+ return -ENOMEM;
+ }
+ return 0;
+}
+subsys_initcall(crash_notes_memory_init);
+
+
+/*
+ * 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;
+
+ /* 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 >= system_ram) {
+ pr_warn("crashkernel: invalid size\n");
+ return -EINVAL;
+ }
+
+ /* match ? */
+ if (system_ram >= start && system_ram < 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;
+ }
+ }
+ }
+
+ 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\n");
+ 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\n");
+ return -EINVAL;
+ }
+ cur += strlen(suffix);
+ if (*cur != ' ' && *cur != '\0') {
+ pr_warn("crashkernel: unrecognized char\n");
+ 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);
+ }
+
+ if (!ck_cmdline)
+ return NULL;
+
+ 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 *name,
+ const char *suffix)
+{
+ char *first_colon, *first_space;
+ char *ck_cmdline;
+
+ BUG_ON(!crash_size || !crash_base);
+ *crash_size = 0;
+ *crash_base = 0;
+
+ ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
+
+ if (!ck_cmdline)
+ return -EINVAL;
+
+ 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.
+ */
+int __init parse_crashkernel(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", NULL);
+}
+
+int __init parse_crashkernel_high(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", suffix_tbl[SUFFIX_HIGH]);
+}
+
+int __init parse_crashkernel_low(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", suffix_tbl[SUFFIX_LOW]);
+}
+
+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_save_vmcoreinfo(void)
+{
+ vmcoreinfo_append_str("CRASHTIME=%ld\n", get_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, vmcoreinfo_max_size - vmcoreinfo_size);
+
+ memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
+
+ vmcoreinfo_size += r;
+}
+
+/*
+ * provide an empty default implementation here -- architecture
+ * code may override this
+ */
+void __weak arch_crash_save_vmcoreinfo(void)
+{}
+
+unsigned long __weak paddr_vmcoreinfo_note(void)
+{
+ return __pa((unsigned long)(char *)&vmcoreinfo_note);
+}
+
+static int __init crash_save_vmcoreinfo_init(void)
+{
+ VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
+ VMCOREINFO_PAGESIZE(PAGE_SIZE);
+
+ VMCOREINFO_SYMBOL(init_uts_ns);
+ VMCOREINFO_SYMBOL(node_online_map);
+#ifdef CONFIG_MMU
+ VMCOREINFO_SYMBOL(swapper_pg_dir);
+#endif
+ VMCOREINFO_SYMBOL(_stext);
+ VMCOREINFO_SYMBOL(vmap_area_list);
+
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+ VMCOREINFO_SYMBOL(mem_map);
+ VMCOREINFO_SYMBOL(contig_page_data);
+#endif
+#ifdef CONFIG_SPARSEMEM
+ VMCOREINFO_SYMBOL(mem_section);
+ VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
+ VMCOREINFO_STRUCT_SIZE(mem_section);
+ VMCOREINFO_OFFSET(mem_section, section_mem_map);
+#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, _count);
+ VMCOREINFO_OFFSET(page, mapping);
+ VMCOREINFO_OFFSET(page, lru);
+ VMCOREINFO_OFFSET(page, _mapcount);
+ VMCOREINFO_OFFSET(page, private);
+ VMCOREINFO_OFFSET(pglist_data, node_zones);
+ VMCOREINFO_OFFSET(pglist_data, nr_zones);
+#ifdef CONFIG_FLAT_NODE_MEM_MAP
+ 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_OFFSET(vmap_area, va_start);
+ VMCOREINFO_OFFSET(vmap_area, list);
+ VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
+ log_buf_kexec_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_slab);
+#ifdef CONFIG_MEMORY_FAILURE
+ VMCOREINFO_NUMBER(PG_hwpoison);
+#endif
+ VMCOREINFO_NUMBER(PG_head_mask);
+ VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+#ifdef CONFIG_HUGETLBFS
+ VMCOREINFO_SYMBOL(free_huge_page);
+#endif
+
+ arch_crash_save_vmcoreinfo();
+ update_vmcoreinfo_note();
+
+ return 0;
+}
+
+subsys_initcall(crash_save_vmcoreinfo_init);
+
+/*
+ * Move into place and start executing a preloaded standalone
+ * executable. If nothing was preloaded return an error.
+ */
+int kernel_kexec(void)
+{
+ int error = 0;
+
+ if (!mutex_trylock(&kexec_mutex))
+ return -EBUSY;
+ if (!kexec_image) {
+ error = -EINVAL;
+ goto Unlock;
+ }
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (kexec_image->preserve_context) {
+ lock_system_sleep();
+ pm_prepare_console();
+ error = freeze_processes();
+ if (error) {
+ error = -EBUSY;
+ goto Restore_console;
+ }
+ suspend_console();
+ error = dpm_suspend_start(PMSG_FREEZE);
+ if (error)
+ goto Resume_console;
+ /* At this point, dpm_suspend_start() has been called,
+ * but *not* dpm_suspend_end(). We *must* call
+ * dpm_suspend_end() now. Otherwise, drivers for
+ * some devices (e.g. interrupt controllers) become
+ * desynchronized with the actual state of the
+ * hardware at resume time, and evil weirdness ensues.
+ */
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error)
+ goto Resume_devices;
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Enable_cpus;
+ local_irq_disable();
+ error = syscore_suspend();
+ if (error)
+ goto Enable_irqs;
+ } else
+#endif
+ {
+ kexec_in_progress = true;
+ kernel_restart_prepare(NULL);
+ migrate_to_reboot_cpu();
+
+ /*
+ * migrate_to_reboot_cpu() disables CPU hotplug assuming that
+ * no further code needs to use CPU hotplug (which is true in
+ * the reboot case). However, the kexec path depends on using
+ * CPU hotplug again; so re-enable it here.
+ */
+ cpu_hotplug_enable();
+ pr_emerg("Starting new kernel\n");
+ machine_shutdown();
+ }
+
+ machine_kexec(kexec_image);
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (kexec_image->preserve_context) {
+ syscore_resume();
+ Enable_irqs:
+ local_irq_enable();
+ Enable_cpus:
+ enable_nonboot_cpus();
+ dpm_resume_start(PMSG_RESTORE);
+ Resume_devices:
+ dpm_resume_end(PMSG_RESTORE);
+ Resume_console:
+ resume_console();
+ thaw_processes();
+ Restore_console:
+ pm_restore_console();
+ unlock_system_sleep();
+ }
+#endif
+
+ Unlock:
+ mutex_unlock(&kexec_mutex);
+ return error;
+}
+
+/*
+ * Add and remove page tables for crashkernel memory
+ *
+ * Provide an empty default implementation here -- architecture
+ * code may override this
+ */
+void __weak crash_map_reserved_pages(void)
+{}
+
+void __weak crash_unmap_reserved_pages(void)
+{}
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 6683cce..e83b264 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -90,7 +90,7 @@ static ssize_t profiling_store(struct kobject *kobj,
KERNEL_ATTR_RW(profiling);
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
static ssize_t kexec_loaded_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
@@ -134,7 +134,7 @@ static ssize_t vmcoreinfo_show(struct kobject *kobj,
}
KERNEL_ATTR_RO(vmcoreinfo);
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
/* whether file capabilities are enabled */
static ssize_t fscaps_show(struct kobject *kobj,
@@ -196,7 +196,7 @@ static struct attribute * kernel_attrs[] = {
#ifdef CONFIG_PROFILING
&profiling_attr.attr,
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
&kexec_loaded_attr.attr,
&kexec_crash_loaded_attr.attr,
&kexec_crash_size_attr.attr,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index cf8c242..8f0324e 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -835,7 +835,7 @@ const struct file_operations kmsg_fops = {
.release = devkmsg_release,
};
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* This appends the listed symbols to /proc/vmcore
*
diff --git a/kernel/reboot.c b/kernel/reboot.c
index d20c85d..bd30a97 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -346,7 +346,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
kernel_restart(buffer);
break;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
case LINUX_REBOOT_CMD_KEXEC:
ret = kernel_kexec();
break;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 19b62b5..715cc57 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -621,7 +621,7 @@ static struct ctl_table kern_table[] = {
.proc_handler = proc_dointvec,
},
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
{
.procname = "kexec_load_disabled",
.data = &kexec_load_disabled,
--
1.8.3.1
On Mon, Jul 13, 2015 at 4:13 AM, <[email protected]> wrote:
> Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
> architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
> KEXEC_CORE in arch Kconfig. Also updated general kernel code with
> to kexec_load syscall.
>
> Signed-off-by: Dave Young <[email protected]>
> ---
> arch/arm/Kconfig | 4 +
> arch/ia64/Kconfig | 4 +
> arch/m68k/Kconfig | 4 +
> arch/mips/Kconfig | 4 +
> arch/powerpc/Kconfig | 4 +
> arch/sh/Kconfig | 4 +
> arch/tile/Kconfig | 4 +
> arch/x86/Kconfig | 6 +-
> arch/x86/boot/header.S | 2 +-
> arch/x86/include/asm/kdebug.h | 2 +-
> arch/x86/kernel/Makefile | 4 +-
> arch/x86/kernel/kvmclock.c | 4 +-
> arch/x86/kernel/reboot.c | 4 +-
> arch/x86/kernel/setup.c | 2 +-
> arch/x86/kernel/vmlinux.lds.S | 2 +-
> arch/x86/kvm/vmx.c | 8 +-
> arch/x86/platform/efi/efi.c | 4 +-
> arch/x86/platform/uv/uv_nmi.c | 6 +-
> drivers/firmware/efi/Kconfig | 2 +-
> drivers/pci/pci-driver.c | 2 +-
> include/linux/kexec.h | 12 +-
> init/initramfs.c | 4 +-
> kernel/Makefile | 1 +
> kernel/events/core.c | 2 +-
> kernel/kexec.c | 1578 +---------------------------------------
> kernel/kexec_core.c | 1594 +++++++++++++++++++++++++++++++++++++++++
> kernel/ksysfs.c | 6 +-
> kernel/printk/printk.c | 2 +-
> kernel/reboot.c | 2 +-
> kernel/sysctl.c | 2 +-
> 30 files changed, 1668 insertions(+), 1611 deletions(-)
> create mode 100644 kernel/kexec_core.c
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 1c50210..20c48b3 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
> be linked for and stored to. This address is dependent on your
> own flash usage.
>
> +config KEXEC_CORE
> + bool
> +
> config KEXEC
> bool "Kexec system call (EXPERIMENTAL)"
> depends on (!SMP || PM_SLEEP_SMP)
> depends on !CPU_V7M
> + select KEXEC_CORE
> help
> kexec is a system call that implements the ability to shutdown your
> current kernel, and to start another kernel. It is like a reboot
As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
and let arch/*/Kconfig select that if the architecture has kexec support.
Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
without the need to duplicate it.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
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
Hi, Geert
Sorry for reply late, I'm occupied by other things.
On 07/13/15 at 10:55am, Geert Uytterhoeven wrote:
> On Mon, Jul 13, 2015 at 4:13 AM, <[email protected]> wrote:
> > Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
> > architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
> > KEXEC_CORE in arch Kconfig. Also updated general kernel code with
> > to kexec_load syscall.
> >
> > Signed-off-by: Dave Young <[email protected]>
> > ---
> > arch/arm/Kconfig | 4 +
> > arch/ia64/Kconfig | 4 +
> > arch/m68k/Kconfig | 4 +
> > arch/mips/Kconfig | 4 +
> > arch/powerpc/Kconfig | 4 +
> > arch/sh/Kconfig | 4 +
> > arch/tile/Kconfig | 4 +
> > arch/x86/Kconfig | 6 +-
> > arch/x86/boot/header.S | 2 +-
> > arch/x86/include/asm/kdebug.h | 2 +-
> > arch/x86/kernel/Makefile | 4 +-
> > arch/x86/kernel/kvmclock.c | 4 +-
> > arch/x86/kernel/reboot.c | 4 +-
> > arch/x86/kernel/setup.c | 2 +-
> > arch/x86/kernel/vmlinux.lds.S | 2 +-
> > arch/x86/kvm/vmx.c | 8 +-
> > arch/x86/platform/efi/efi.c | 4 +-
> > arch/x86/platform/uv/uv_nmi.c | 6 +-
> > drivers/firmware/efi/Kconfig | 2 +-
> > drivers/pci/pci-driver.c | 2 +-
> > include/linux/kexec.h | 12 +-
> > init/initramfs.c | 4 +-
> > kernel/Makefile | 1 +
> > kernel/events/core.c | 2 +-
> > kernel/kexec.c | 1578 +---------------------------------------
> > kernel/kexec_core.c | 1594 +++++++++++++++++++++++++++++++++++++++++
> > kernel/ksysfs.c | 6 +-
> > kernel/printk/printk.c | 2 +-
> > kernel/reboot.c | 2 +-
> > kernel/sysctl.c | 2 +-
> > 30 files changed, 1668 insertions(+), 1611 deletions(-)
> > create mode 100644 kernel/kexec_core.c
> >
> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > index 1c50210..20c48b3 100644
> > --- a/arch/arm/Kconfig
> > +++ b/arch/arm/Kconfig
> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
> > be linked for and stored to. This address is dependent on your
> > own flash usage.
> >
> > +config KEXEC_CORE
> > + bool
> > +
> > config KEXEC
> > bool "Kexec system call (EXPERIMENTAL)"
> > depends on (!SMP || PM_SLEEP_SMP)
> > depends on !CPU_V7M
> > + select KEXEC_CORE
> > help
> > kexec is a system call that implements the ability to shutdown your
> > current kernel, and to start another kernel. It is like a reboot
>
> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
> and let arch/*/Kconfig select that if the architecture has kexec support.
>
> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
> without the need to duplicate it.
I'm not sure I understand your idea well, do you means like
in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
How about simply move below chunk to arch/Kconfig instead of introducing
another ARCH_HAS_KEXEC:
config KEXEC_CORE
bool
BTW, I found I missed one arch that is s390, I need update the patches
and resend.
Thanks
Dave
Hi Dave,
On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
>> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> > index 1c50210..20c48b3 100644
>> > --- a/arch/arm/Kconfig
>> > +++ b/arch/arm/Kconfig
>> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
>> > be linked for and stored to. This address is dependent on your
>> > own flash usage.
>> >
>> > +config KEXEC_CORE
>> > + bool
>> > +
>> > config KEXEC
>> > bool "Kexec system call (EXPERIMENTAL)"
>> > depends on (!SMP || PM_SLEEP_SMP)
>> > depends on !CPU_V7M
>> > + select KEXEC_CORE
>> > help
>> > kexec is a system call that implements the ability to shutdown your
>> > current kernel, and to start another kernel. It is like a reboot
>>
>> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
>> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
>> and let arch/*/Kconfig select that if the architecture has kexec support.
>>
>> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
>> without the need to duplicate it.
>
> I'm not sure I understand your idea well, do you means like
> in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
All other KEXEC config options should depend on ARCH_HAS_KEXEC,
which can be selected by architectures that support kexec.
> How about simply move below chunk to arch/Kconfig instead of introducing
> another ARCH_HAS_KEXEC:
> config KEXEC_CORE
> bool
Not all architectures support kexec, hence my proposed dependency on
ARCH_HAS_KEXEC.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
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
On 07/14/15 at 10:50am, Geert Uytterhoeven wrote:
> Hi Dave,
>
> On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
> >> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> > index 1c50210..20c48b3 100644
> >> > --- a/arch/arm/Kconfig
> >> > +++ b/arch/arm/Kconfig
> >> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
> >> > be linked for and stored to. This address is dependent on your
> >> > own flash usage.
> >> >
> >> > +config KEXEC_CORE
> >> > + bool
> >> > +
> >> > config KEXEC
> >> > bool "Kexec system call (EXPERIMENTAL)"
> >> > depends on (!SMP || PM_SLEEP_SMP)
> >> > depends on !CPU_V7M
> >> > + select KEXEC_CORE
> >> > help
> >> > kexec is a system call that implements the ability to shutdown your
> >> > current kernel, and to start another kernel. It is like a reboot
> >>
> >> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
> >> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
> >> and let arch/*/Kconfig select that if the architecture has kexec support.
> >>
> >> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
> >> without the need to duplicate it.
> >
> > I'm not sure I understand your idea well, do you means like
> > in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
>
> No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
> All other KEXEC config options should depend on ARCH_HAS_KEXEC,
> which can be selected by architectures that support kexec.
So it will be like below? problem is KEXEC_FILE is x86 only now, how
to handle it then?
arch/Kconfig:
config ARCH_HAS_KEXEC
...
config KEXEC_CORE
...
config KEXEC
...
config KEXEC_FILE
...
arch/arm/Kconfig:
select ARCH_HAS_KEXEC
>
> > How about simply move below chunk to arch/Kconfig instead of introducing
> > another ARCH_HAS_KEXEC:
> > config KEXEC_CORE
> > bool
>
> Not all architectures support kexec, hence my proposed dependency on
> ARCH_HAS_KEXEC.
KEXEC_CORE is not visible in menuconfig, it is selected by KEXEC and KEXEC_FILE
so move it in arch/Kconfig is ok?
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
>
> 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
Hi Dave,
On Tue, Jul 14, 2015 at 11:11 AM, Dave Young <[email protected]> wrote:
> On 07/14/15 at 10:50am, Geert Uytterhoeven wrote:
>> On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
>> >> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> >> > index 1c50210..20c48b3 100644
>> >> > --- a/arch/arm/Kconfig
>> >> > +++ b/arch/arm/Kconfig
>> >> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
>> >> > be linked for and stored to. This address is dependent on your
>> >> > own flash usage.
>> >> >
>> >> > +config KEXEC_CORE
>> >> > + bool
>> >> > +
>> >> > config KEXEC
>> >> > bool "Kexec system call (EXPERIMENTAL)"
>> >> > depends on (!SMP || PM_SLEEP_SMP)
>> >> > depends on !CPU_V7M
>> >> > + select KEXEC_CORE
>> >> > help
>> >> > kexec is a system call that implements the ability to shutdown your
>> >> > current kernel, and to start another kernel. It is like a reboot
>> >>
>> >> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
>> >> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
>> >> and let arch/*/Kconfig select that if the architecture has kexec support.
>> >>
>> >> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
>> >> without the need to duplicate it.
>> >
>> > I'm not sure I understand your idea well, do you means like
>> > in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
>>
>> No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
>> All other KEXEC config options should depend on ARCH_HAS_KEXEC,
>> which can be selected by architectures that support kexec.
>
> So it will be like below? problem is KEXEC_FILE is x86 only now, how
> to handle it then?
>
> arch/Kconfig:
> config ARCH_HAS_KEXEC
> ...
> config KEXEC_CORE
> ...
> config KEXEC
depends on ARCH_HAS_KEXEC
> ...
> config KEXEC_FILE
depends on ARCH_HAS_KEXEC
> ...
>
> arch/arm/Kconfig:
> select ARCH_HAS_KEXEC
Right, that's the idea.
(Minor nit: ARM has dependencies for kexec, so it should be
"select ARCH_HAS_KEXEC if (!SMP || PM_SLEEP_SMP) && !CPU_V7M")
>> > How about simply move below chunk to arch/Kconfig instead of introducing
>> > another ARCH_HAS_KEXEC:
>> > config KEXEC_CORE
>> > bool
>>
>> Not all architectures support kexec, hence my proposed dependency on
>> ARCH_HAS_KEXEC.
>
> KEXEC_CORE is not visible in menuconfig, it is selected by KEXEC and KEXEC_FILE
> so move it in arch/Kconfig is ok?
Yes.
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
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
Hi, Geert
On 07/14/15 at 11:16am, Geert Uytterhoeven wrote:
> Hi Dave,
>
> On Tue, Jul 14, 2015 at 11:11 AM, Dave Young <[email protected]> wrote:
> > On 07/14/15 at 10:50am, Geert Uytterhoeven wrote:
> >> On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
> >> >> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> >> > index 1c50210..20c48b3 100644
> >> >> > --- a/arch/arm/Kconfig
> >> >> > +++ b/arch/arm/Kconfig
> >> >> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
> >> >> > be linked for and stored to. This address is dependent on your
> >> >> > own flash usage.
> >> >> >
> >> >> > +config KEXEC_CORE
> >> >> > + bool
> >> >> > +
> >> >> > config KEXEC
> >> >> > bool "Kexec system call (EXPERIMENTAL)"
> >> >> > depends on (!SMP || PM_SLEEP_SMP)
> >> >> > depends on !CPU_V7M
> >> >> > + select KEXEC_CORE
> >> >> > help
> >> >> > kexec is a system call that implements the ability to shutdown your
> >> >> > current kernel, and to start another kernel. It is like a reboot
> >> >>
> >> >> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
> >> >> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
> >> >> and let arch/*/Kconfig select that if the architecture has kexec support.
> >> >>
> >> >> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
> >> >> without the need to duplicate it.
> >> >
> >> > I'm not sure I understand your idea well, do you means like
> >> > in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
> >>
> >> No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
> >> All other KEXEC config options should depend on ARCH_HAS_KEXEC,
> >> which can be selected by architectures that support kexec.
> >
> > So it will be like below? problem is KEXEC_FILE is x86 only now, how
> > to handle it then?
> >
> > arch/Kconfig:
> > config ARCH_HAS_KEXEC
> > ...
> > config KEXEC_CORE
> > ...
> > config KEXEC
>
> depends on ARCH_HAS_KEXEC
>
> > ...
> > config KEXEC_FILE
>
> depends on ARCH_HAS_KEXEC
But only x86 has KEXEC_FILE, if we make this change one will see KEXEC_FILE
on arches other than x86..
>
> > ...
> >
> > arch/arm/Kconfig:
> > select ARCH_HAS_KEXEC
>
> Right, that's the idea.
>
> (Minor nit: ARM has dependencies for kexec, so it should be
> "select ARCH_HAS_KEXEC if (!SMP || PM_SLEEP_SMP) && !CPU_V7M")
>
> >> > How about simply move below chunk to arch/Kconfig instead of introducing
> >> > another ARCH_HAS_KEXEC:
> >> > config KEXEC_CORE
> >> > bool
> >>
> >> Not all architectures support kexec, hence my proposed dependency on
> >> ARCH_HAS_KEXEC.
> >
> > KEXEC_CORE is not visible in menuconfig, it is selected by KEXEC and KEXEC_FILE
> > so move it in arch/Kconfig is ok?
>
> Yes.
I means how about only moving KEXEC_CORE to general Kconfig, but do not introduce
ARCH_HAS_KEXEC..
Thanks
Dave
Hi Dave,
On Tue, Jul 14, 2015 at 11:24 AM, Dave Young <[email protected]> wrote:
> On 07/14/15 at 11:16am, Geert Uytterhoeven wrote:
>> On Tue, Jul 14, 2015 at 11:11 AM, Dave Young <[email protected]> wrote:
>> > On 07/14/15 at 10:50am, Geert Uytterhoeven wrote:
>> >> On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
>> >> >> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> >> >> > index 1c50210..20c48b3 100644
>> >> >> > --- a/arch/arm/Kconfig
>> >> >> > +++ b/arch/arm/Kconfig
>> >> >> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
>> >> >> > be linked for and stored to. This address is dependent on your
>> >> >> > own flash usage.
>> >> >> >
>> >> >> > +config KEXEC_CORE
>> >> >> > + bool
>> >> >> > +
>> >> >> > config KEXEC
>> >> >> > bool "Kexec system call (EXPERIMENTAL)"
>> >> >> > depends on (!SMP || PM_SLEEP_SMP)
>> >> >> > depends on !CPU_V7M
>> >> >> > + select KEXEC_CORE
>> >> >> > help
>> >> >> > kexec is a system call that implements the ability to shutdown your
>> >> >> > current kernel, and to start another kernel. It is like a reboot
>> >> >>
>> >> >> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
>> >> >> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
>> >> >> and let arch/*/Kconfig select that if the architecture has kexec support.
>> >> >>
>> >> >> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
>> >> >> without the need to duplicate it.
>> >> >
>> >> > I'm not sure I understand your idea well, do you means like
>> >> > in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
>> >>
>> >> No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
>> >> All other KEXEC config options should depend on ARCH_HAS_KEXEC,
>> >> which can be selected by architectures that support kexec.
>> >
>> > So it will be like below? problem is KEXEC_FILE is x86 only now, how
>> > to handle it then?
>> >
>> > arch/Kconfig:
>> > config ARCH_HAS_KEXEC
>> > ...
>> > config KEXEC_CORE
>> > ...
>> > config KEXEC
>>
>> depends on ARCH_HAS_KEXEC
>>
>> > ...
>> > config KEXEC_FILE
>>
>> depends on ARCH_HAS_KEXEC
>
> But only x86 has KEXEC_FILE, if we make this change one will see KEXEC_FILE
> on arches other than x86..
Is there any technical reason why it's limited to x86?
Else we may need ARCH_HAS_KEXEC_FILE, too :-(
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
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
Hi, Geert
On 07/14/15 at 11:47am, Geert Uytterhoeven wrote:
> Hi Dave,
>
> On Tue, Jul 14, 2015 at 11:24 AM, Dave Young <[email protected]> wrote:
> > On 07/14/15 at 11:16am, Geert Uytterhoeven wrote:
> >> On Tue, Jul 14, 2015 at 11:11 AM, Dave Young <[email protected]> wrote:
> >> > On 07/14/15 at 10:50am, Geert Uytterhoeven wrote:
> >> >> On Tue, Jul 14, 2015 at 10:46 AM, Dave Young <[email protected]> wrote:
> >> >> >> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> >> >> > index 1c50210..20c48b3 100644
> >> >> >> > --- a/arch/arm/Kconfig
> >> >> >> > +++ b/arch/arm/Kconfig
> >> >> >> > @@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
> >> >> >> > be linked for and stored to. This address is dependent on your
> >> >> >> > own flash usage.
> >> >> >> >
> >> >> >> > +config KEXEC_CORE
> >> >> >> > + bool
> >> >> >> > +
> >> >> >> > config KEXEC
> >> >> >> > bool "Kexec system call (EXPERIMENTAL)"
> >> >> >> > depends on (!SMP || PM_SLEEP_SMP)
> >> >> >> > depends on !CPU_V7M
> >> >> >> > + select KEXEC_CORE
> >> >> >> > help
> >> >> >> > kexec is a system call that implements the ability to shutdown your
> >> >> >> > current kernel, and to start another kernel. It is like a reboot
> >> >> >>
> >> >> >> As this KEXEC_CORE is appearing in all arch/*/Kconfig files, I think it's
> >> >> >> time to add an ARCH_HAS_KEXEC symbol (to a common Kconfig file),
> >> >> >> and let arch/*/Kconfig select that if the architecture has kexec support.
> >> >> >>
> >> >> >> Then KEXEC and KEXEC_CORE can live in the common Kconfig file,
> >> >> >> without the need to duplicate it.
> >> >> >
> >> >> > I'm not sure I understand your idea well, do you means like
> >> >> > in arch/Kconfig add ARCH_HAS_KEXEC which depends on KEXEC_CORE?
> >> >>
> >> >> No, ARCH_HAS_KEXEC and all other KEXEC config options in arch/Kconfig.
> >> >> All other KEXEC config options should depend on ARCH_HAS_KEXEC,
> >> >> which can be selected by architectures that support kexec.
> >> >
> >> > So it will be like below? problem is KEXEC_FILE is x86 only now, how
> >> > to handle it then?
> >> >
> >> > arch/Kconfig:
> >> > config ARCH_HAS_KEXEC
> >> > ...
> >> > config KEXEC_CORE
> >> > ...
> >> > config KEXEC
> >>
> >> depends on ARCH_HAS_KEXEC
> >>
> >> > ...
> >> > config KEXEC_FILE
> >>
> >> depends on ARCH_HAS_KEXEC
> >
> > But only x86 has KEXEC_FILE, if we make this change one will see KEXEC_FILE
> > on arches other than x86..
>
> Is there any technical reason why it's limited to x86?
It was implemented for UEFI secure boot, til now only done in x86. Of course it
is also doable for other archtecture even if there's no secure boot. Basiclly
one need port the userspace code in kexec-tools to kernel space, also need code
to verify kernel signature.
> Else we may need ARCH_HAS_KEXEC_FILE, too :-(
Hmm, I'm not sure it will have much benefits now to add two ARCH_HAS options.
I would prefer current solution, but I can move the KEXEC_CORE to arch/Kconfig
Thanks
Dave