From: Anup Patel <[email protected]>
This patchset does:
1. Moves MM related code from kernel/setup.c to mm/init.c
2. Implements compile-time fixed mappings
Using fixed mappings available, we can now get earlyprints
even without SBI calls. For example, we can use kernel
parameter "earlycon=uart8250,mmio,0x10000000" to get early
prints on QEMU virt machine without using SBI calls.
The patchset is tested on QEMU virt machine. It is based on
Linux-5.0-rc6 and can be found at riscv_fixmap_v3 branch of:
https://github.com/avpatel/linux.git.
Changes since v2:
- Fixed commit description of PATCH6
- Ensured commit description of all PATCH use upto 72
characters per line
Changes since v1:
- Use more characters per line in changelog of PATCH3
- Removed #ifndef __ASSEMBLY__ from PATCH5
- Use more characters per line in commets of PATCH5
- Added PATCH6 to implement keepinitrd kernel parameter
Anup Patel (6):
RISC-V: Move free_initrd_mem() to kernel/setup.c
RISC-V: Setup init_mm before parse_early_param()
RISC-V: Move setup_bootmem() to mm/init.c
RISC-V: Move setup_vm() to mm/init.c
RISC-V: Implement compile-time fixed mappings
RISC-V: Implement keepinitrd kernel parameter
arch/riscv/Kconfig | 3 +
arch/riscv/include/asm/fixmap.h | 44 +++++++++++
arch/riscv/include/asm/pgtable.h | 1 +
arch/riscv/kernel/setup.c | 114 ++++++----------------------
arch/riscv/mm/init.c | 124 ++++++++++++++++++++++++++++++-
5 files changed, 189 insertions(+), 97 deletions(-)
create mode 100644 arch/riscv/include/asm/fixmap.h
--
2.17.1
We move free_initrd_mem() to kernel/setup.c so that all initrd related
functions are in one place.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
arch/riscv/kernel/setup.c | 4 ++++
arch/riscv/mm/init.c | 7 -------
2 files changed, 4 insertions(+), 7 deletions(-)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 77564310235f..36f60b4d2147 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -96,6 +96,10 @@ static void __init setup_initrd(void)
initrd_start = 0;
initrd_end = 0;
}
+
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+}
#endif /* CONFIG_BLK_DEV_INITRD */
pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 658ebf645f42..504a5e491f5a 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -14,7 +14,6 @@
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memblock.h>
-#include <linux/initrd.h>
#include <linux/swap.h>
#include <linux/sizes.h>
@@ -64,9 +63,3 @@ void free_initmem(void)
{
free_initmem_default(0);
}
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
--
2.17.1
We should setup init_mm before doing parse_early_param() in setup_arch()
to be consistent with setup_arch() of other architectures such as x86,
ARM, and ARM64.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
arch/riscv/kernel/setup.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 36f60b4d2147..9e6395b7d409 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -208,15 +208,15 @@ static void __init setup_bootmem(void)
void __init setup_arch(char **cmdline_p)
{
- *cmdline_p = boot_command_line;
-
- parse_early_param();
-
init_mm.start_code = (unsigned long) _stext;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = (unsigned long) _end;
+ *cmdline_p = boot_command_line;
+
+ parse_early_param();
+
setup_bootmem();
paging_init();
unflatten_device_tree();
@@ -235,4 +235,3 @@ void __init setup_arch(char **cmdline_p)
riscv_fill_hwcap();
}
-
--
2.17.1
The setup_bootmem() mainly populates memblocks and does early memory
reservations. The right location for this function is mm/init.c.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
arch/riscv/include/asm/pgtable.h | 1 +
arch/riscv/kernel/setup.c | 48 ++++----------------------------
arch/riscv/mm/init.c | 40 ++++++++++++++++++++++++++
3 files changed, 46 insertions(+), 43 deletions(-)
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 16301966d65b..35893810cba3 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -404,6 +404,7 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
#define kern_addr_valid(addr) (1) /* FIXME */
#endif
+extern void setup_bootmem(void);
extern void paging_init(void);
static inline void pgtable_cache_init(void)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 9e6395b7d409..ab29a66a17fc 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -163,49 +163,6 @@ void __init parse_dtb(unsigned int hartid, void *dtb)
#endif
}
-static void __init setup_bootmem(void)
-{
- struct memblock_region *reg;
- phys_addr_t mem_size = 0;
-
- /* Find the memory region containing the kernel */
- for_each_memblock(memory, reg) {
- phys_addr_t vmlinux_end = __pa(_end);
- phys_addr_t end = reg->base + reg->size;
-
- if (reg->base <= vmlinux_end && vmlinux_end <= end) {
- /*
- * Reserve from the start of the region to the end of
- * the kernel
- */
- memblock_reserve(reg->base, vmlinux_end - reg->base);
- mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
- }
- }
- BUG_ON(mem_size == 0);
-
- set_max_mapnr(PFN_DOWN(mem_size));
- max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
-
-#ifdef CONFIG_BLK_DEV_INITRD
- setup_initrd();
-#endif /* CONFIG_BLK_DEV_INITRD */
-
- early_init_fdt_reserve_self();
- early_init_fdt_scan_reserved_mem();
- memblock_allow_resize();
- memblock_dump_all();
-
- for_each_memblock(memory, reg) {
- unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
- unsigned long end_pfn = memblock_region_memory_end_pfn(reg);
-
- memblock_set_node(PFN_PHYS(start_pfn),
- PFN_PHYS(end_pfn - start_pfn),
- &memblock.memory, 0);
- }
-}
-
void __init setup_arch(char **cmdline_p)
{
init_mm.start_code = (unsigned long) _stext;
@@ -218,6 +175,11 @@ void __init setup_arch(char **cmdline_p)
parse_early_param();
setup_bootmem();
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ setup_initrd();
+#endif /* CONFIG_BLK_DEV_INITRD */
+
paging_init();
unflatten_device_tree();
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 504a5e491f5a..a57dba8ac9e7 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -16,6 +16,7 @@
#include <linux/memblock.h>
#include <linux/swap.h>
#include <linux/sizes.h>
+#include <linux/of_fdt.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
@@ -63,3 +64,42 @@ void free_initmem(void)
{
free_initmem_default(0);
}
+
+void __init setup_bootmem(void)
+{
+ struct memblock_region *reg;
+ phys_addr_t mem_size = 0;
+
+ /* Find the memory region containing the kernel */
+ for_each_memblock(memory, reg) {
+ phys_addr_t vmlinux_end = __pa(_end);
+ phys_addr_t end = reg->base + reg->size;
+
+ if (reg->base <= vmlinux_end && vmlinux_end <= end) {
+ /*
+ * Reserve from the start of the region to the end of
+ * the kernel
+ */
+ memblock_reserve(reg->base, vmlinux_end - reg->base);
+ mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
+ }
+ }
+ BUG_ON(mem_size == 0);
+
+ set_max_mapnr(PFN_DOWN(mem_size));
+ max_low_pfn = memblock_end_of_DRAM();
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+ memblock_allow_resize();
+ memblock_dump_all();
+
+ for_each_memblock(memory, reg) {
+ unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
+ unsigned long end_pfn = memblock_region_memory_end_pfn(reg);
+
+ memblock_set_node(PFN_PHYS(start_pfn),
+ PFN_PHYS(end_pfn - start_pfn),
+ &memblock.memory, 0);
+ }
+}
--
2.17.1
The setup_vm() is responsible for setting up initial page table hence
should be placed in mm/init.c.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
arch/riscv/kernel/setup.c | 49 ---------------------------------------
arch/riscv/mm/init.c | 49 +++++++++++++++++++++++++++++++++++++++
2 files changed, 49 insertions(+), 49 deletions(-)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index ab29a66a17fc..9cd583b6d1cd 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -102,55 +102,6 @@ void free_initrd_mem(unsigned long start, unsigned long end)
}
#endif /* CONFIG_BLK_DEV_INITRD */
-pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
-pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
-
-#ifndef __PAGETABLE_PMD_FOLDED
-#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
-pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
-pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
-#endif
-
-asmlinkage void __init setup_vm(void)
-{
- extern char _start;
- uintptr_t i;
- uintptr_t pa = (uintptr_t) &_start;
- pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC);
-
- va_pa_offset = PAGE_OFFSET - pa;
- pfn_base = PFN_DOWN(pa);
-
- /* Sanity check alignment and size */
- BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
- BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);
-
-#ifndef __PAGETABLE_PMD_FOLDED
- trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
- pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
- __pgprot(_PAGE_TABLE));
- trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);
-
- for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
- size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
- swapper_pg_dir[o] =
- pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
- __pgprot(_PAGE_TABLE));
- }
- for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
- swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
-#else
- trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
- pfn_pgd(PFN_DOWN(pa), prot);
-
- for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
- size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
- swapper_pg_dir[o] =
- pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
- }
-#endif
-}
-
void __init parse_dtb(unsigned int hartid, void *dtb)
{
if (!early_init_dt_scan(__va(dtb)))
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index a57dba8ac9e7..7ed6ae90cf6b 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -103,3 +103,52 @@ void __init setup_bootmem(void)
&memblock.memory, 0);
}
}
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
+pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
+pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+#endif
+
+asmlinkage void __init setup_vm(void)
+{
+ extern char _start;
+ uintptr_t i;
+ uintptr_t pa = (uintptr_t) &_start;
+ pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC);
+
+ va_pa_offset = PAGE_OFFSET - pa;
+ pfn_base = PFN_DOWN(pa);
+
+ /* Sanity check alignment and size */
+ BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
+ BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
+ __pgprot(_PAGE_TABLE));
+ trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);
+
+ for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
+ size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+ swapper_pg_dir[o] =
+ pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
+ __pgprot(_PAGE_TABLE));
+ }
+ for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
+ swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
+#else
+ trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN(pa), prot);
+
+ for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
+ size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+ swapper_pg_dir[o] =
+ pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
+ }
+#endif
+}
--
2.17.1
This patch implements compile-time virtual to physical mappings. These
compile-time fixed mappings can be used by earlycon, ACPI, and early
ioremap for creating fixed mappings when FIX_EARLYCON_MEM=y.
To start with, we have enabled compile-time fixed mappings for earlycon.
Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
arch/riscv/Kconfig | 3 +++
arch/riscv/include/asm/fixmap.h | 44 +++++++++++++++++++++++++++++++++
arch/riscv/mm/init.c | 34 +++++++++++++++++++++++++
3 files changed, 81 insertions(+)
create mode 100644 arch/riscv/include/asm/fixmap.h
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 515fc3cc9687..3cfd10d35a28 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -89,6 +89,9 @@ config GENERIC_CSUM
config GENERIC_HWEIGHT
def_bool y
+config FIX_EARLYCON_MEM
+ def_bool y
+
config PGTABLE_LEVELS
int
default 3 if 64BIT
diff --git a/arch/riscv/include/asm/fixmap.h b/arch/riscv/include/asm/fixmap.h
new file mode 100644
index 000000000000..57afe604b495
--- /dev/null
+++ b/arch/riscv/include/asm/fixmap.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ */
+
+#ifndef _ASM_RISCV_FIXMAP_H
+#define _ASM_RISCV_FIXMAP_H
+
+#include <linux/kernel.h>
+#include <linux/sizes.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+/*
+ * Here we define all the compile-time 'special' virtual addresses.
+ * The point is to have a constant address at compile time, but to
+ * set the physical address only in the boot process.
+ *
+ * These 'compile-time allocated' memory buffers are page-sized. Use
+ * set_fixmap(idx,phys) to associate physical memory with fixmap indices.
+ */
+enum fixed_addresses {
+ FIX_HOLE,
+ FIX_EARLYCON_MEM_BASE,
+ __end_of_fixed_addresses
+};
+
+#define FIXADDR_SIZE (__end_of_fixed_addresses * PAGE_SIZE)
+#define FIXADDR_TOP (PAGE_OFFSET)
+#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
+
+#define FIXMAP_PAGE_IO PAGE_KERNEL
+
+#define __early_set_fixmap __set_fixmap
+
+#define __late_set_fixmap __set_fixmap
+#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
+
+extern void __set_fixmap(enum fixed_addresses idx,
+ phys_addr_t phys, pgprot_t prot);
+
+#include <asm-generic/fixmap.h>
+
+#endif /* _ASM_RISCV_FIXMAP_H */
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 7ed6ae90cf6b..efcbdb9b3da3 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -18,6 +18,7 @@
#include <linux/sizes.h>
#include <linux/of_fdt.h>
+#include <asm/fixmap.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
@@ -111,8 +112,28 @@ pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
#endif
+pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
+
+void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
+{
+ unsigned long addr = __fix_to_virt(idx);
+ pte_t *ptep;
+
+ BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
+
+ ptep = &fixmap_pte[pte_index(addr)];
+
+ if (pgprot_val(prot)) {
+ set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
+ } else {
+ pte_clear(&init_mm, addr, ptep);
+ local_flush_tlb_page(addr);
+ }
+}
+
asmlinkage void __init setup_vm(void)
{
extern char _start;
@@ -135,20 +156,33 @@ asmlinkage void __init setup_vm(void)
for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+
swapper_pg_dir[o] =
pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
__pgprot(_PAGE_TABLE));
}
for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
+
+ swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pmd),
+ __pgprot(_PAGE_TABLE));
+ fixmap_pmd[(FIXADDR_START >> PMD_SHIFT) % PTRS_PER_PMD] =
+ pfn_pmd(PFN_DOWN((uintptr_t)fixmap_pte),
+ __pgprot(_PAGE_TABLE));
#else
trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
pfn_pgd(PFN_DOWN(pa), prot);
for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
+
swapper_pg_dir[o] =
pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
}
+
+ swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] =
+ pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pte),
+ __pgprot(_PAGE_TABLE));
#endif
}
--
2.17.1
This patch implements keepinitrd kernel parameter. By default,
keepinitrd=0 so initrd memory will be freed by default freed but
users can pass "keepinitrd=1" to keep the initrd memory.
The keepinitrd kernel parameter is already implemented by unicore32,
arm, and arm64 architectures and it is documented at:
Documentation/admin-guide/kernel-parameters.txt
Signed-off-by: Anup Patel <[email protected]>
---
arch/riscv/kernel/setup.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 9cd583b6d1cd..46e547dd8245 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -97,8 +97,20 @@ static void __init setup_initrd(void)
initrd_end = 0;
}
-void free_initrd_mem(unsigned long start, unsigned long end)
+static int keep_initrd __initdata;
+
+static int __init keepinitrd_setup(char *__unused)
+{
+ keep_initrd = 1;
+ return 1;
+}
+
+__setup("keepinitrd", keepinitrd_setup);
+
+void __init free_initrd_mem(unsigned long start, unsigned long end)
{
+ if (!keep_initrd)
+ memblock_free(__pa(start), end - start);
}
#endif /* CONFIG_BLK_DEV_INITRD */
--
2.17.1
On Feb 12 2019, Anup Patel <[email protected]> wrote:
> This patch implements keepinitrd kernel parameter. By default,
> keepinitrd=0 so initrd memory will be freed by default freed but
-freed
Andreas.
--
Andreas Schwab, SUSE Labs, [email protected]
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."