| Message ID | 20200801130856.86625-3-chenzhou10@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | support reserving crashkernel above 4G on arm64 kdump | expand |
* Chen Zhou <chenzhou10@huawei.com> wrote: > In preparation for supporting reserve_crashkernel_low in arm64 as > x86_64 does, move reserve_crashkernel_low() into kernel/crash_core.c. > > BTW, move x86_64 CRASH_ALIGN to 2M suggested by Dave. CONFIG_PHYSICAL_ALIGN > can be selected from 2M to 16M, move to the same as arm64. > > Signed-off-by: Chen Zhou <chenzhou10@huawei.com> > --- > arch/x86/include/asm/kexec.h | 24 ++++++++++ > arch/x86/kernel/setup.c | 86 +++--------------------------------- > include/linux/crash_core.h | 3 ++ > include/linux/kexec.h | 2 - > kernel/crash_core.c | 74 +++++++++++++++++++++++++++++++ > kernel/kexec_core.c | 17 ------- > 6 files changed, 107 insertions(+), 99 deletions(-) Since the changes are centered around arm64, I suppose the arm64 tree will carry this patchset? Assuming that this is a 100% invariant moving of code that doesn't regress on x86: Acked-by: Ingo Molnar <mingo@kernel.org> Thanks, Ingo
On 08/01/20 at 09:08pm, Chen Zhou wrote: > In preparation for supporting reserve_crashkernel_low in arm64 as > x86_64 does, move reserve_crashkernel_low() into kernel/crash_core.c. > > BTW, move x86_64 CRASH_ALIGN to 2M suggested by Dave. CONFIG_PHYSICAL_ALIGN > can be selected from 2M to 16M, move to the same as arm64. > > Signed-off-by: Chen Zhou <chenzhou10@huawei.com> > --- > arch/x86/include/asm/kexec.h | 24 ++++++++++ > arch/x86/kernel/setup.c | 86 +++--------------------------------- > include/linux/crash_core.h | 3 ++ > include/linux/kexec.h | 2 - > kernel/crash_core.c | 74 +++++++++++++++++++++++++++++++ > kernel/kexec_core.c | 17 ------- > 6 files changed, 107 insertions(+), 99 deletions(-) > > diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h > index 6802c59e8252..f8f9d952e09f 100644 > --- a/arch/x86/include/asm/kexec.h > +++ b/arch/x86/include/asm/kexec.h > @@ -18,6 +18,30 @@ > > # define KEXEC_CONTROL_CODE_MAX_SIZE 2048 > > +/* 2M alignment for crash kernel regions */ > +#define CRASH_ALIGN SZ_2M > + > +/* > + * Keep the crash kernel below this limit. > + * > + * Earlier 32-bits kernels would limit the kernel to the low 512 MB range > + * due to mapping restrictions. > + * > + * 64-bit kdump kernels need to be restricted to be under 64 TB, which is > + * the upper limit of system RAM in 4-level paging mode. Since the kdump > + * jump could be from 5-level paging to 4-level paging, the jump will fail if > + * the kernel is put above 64 TB, and during the 1st kernel bootup there's > + * no good way to detect the paging mode of the target kernel which will be > + * loaded for dumping. > + */ > +#ifdef CONFIG_X86_32 > +# define CRASH_ADDR_LOW_MAX SZ_512M > +# define CRASH_ADDR_HIGH_MAX SZ_512M > +#else > +# define CRASH_ADDR_LOW_MAX SZ_4G > +# define CRASH_ADDR_HIGH_MAX SZ_64T > +#endif > + > #ifndef __ASSEMBLY__ > > #include <linux/string.h> > diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c > index a3767e74c758..46763c1e5d9f 100644 > --- a/arch/x86/kernel/setup.c > +++ b/arch/x86/kernel/setup.c > @@ -401,83 +401,6 @@ static void __init memblock_x86_reserve_range_setup_data(void) > > #ifdef CONFIG_KEXEC_CORE > > -/* 16M alignment for crash kernel regions */ > -#define CRASH_ALIGN SZ_16M > - > -/* > - * Keep the crash kernel below this limit. > - * > - * Earlier 32-bits kernels would limit the kernel to the low 512 MB range > - * due to mapping restrictions. > - * > - * 64-bit kdump kernels need to be restricted to be under 64 TB, which is > - * the upper limit of system RAM in 4-level paging mode. Since the kdump > - * jump could be from 5-level paging to 4-level paging, the jump will fail if > - * the kernel is put above 64 TB, and during the 1st kernel bootup there's > - * no good way to detect the paging mode of the target kernel which will be > - * loaded for dumping. > - */ > -#ifdef CONFIG_X86_32 > -# define CRASH_ADDR_LOW_MAX SZ_512M > -# define CRASH_ADDR_HIGH_MAX SZ_512M > -#else > -# define CRASH_ADDR_LOW_MAX SZ_4G > -# define CRASH_ADDR_HIGH_MAX SZ_64T > -#endif > - > -static int __init reserve_crashkernel_low(void) > -{ > -#ifdef CONFIG_X86_64 > - unsigned long long base, low_base = 0, low_size = 0; > - unsigned long total_low_mem; > - int ret; > - > - total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT)); > - > - /* crashkernel=Y,low */ > - ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base); > - if (ret) { > - /* > - * two parts from kernel/dma/swiotlb.c: > - * -swiotlb size: user-specified with swiotlb= or default. > - * > - * -swiotlb overflow buffer: now hardcoded to 32k. We round it > - * to 8M for other buffers that may need to stay low too. Also > - * make sure we allocate enough extra low memory so that we > - * don't run out of DMA buffers for 32-bit devices. > - */ > - low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); > - } else { > - /* passed with crashkernel=0,low ? */ > - if (!low_size) > - return 0; > - } > - > - low_base = memblock_find_in_range(0, 1ULL << 32, low_size, CRASH_ALIGN); > - if (!low_base) { > - pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", > - (unsigned long)(low_size >> 20)); > - return -ENOMEM; > - } > - > - ret = memblock_reserve(low_base, low_size); > - if (ret) { > - pr_err("%s: Error reserving crashkernel low memblock.\n", __func__); > - return ret; > - } > - > - pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", > - (unsigned long)(low_size >> 20), > - (unsigned long)(low_base >> 20), > - (unsigned long)(total_low_mem >> 20)); > - > - crashk_low_res.start = low_base; > - crashk_low_res.end = low_base + low_size - 1; > - insert_resource(&iomem_resource, &crashk_low_res); > -#endif > - return 0; > -} > - > static void __init reserve_crashkernel(void) > { > unsigned long long crash_size, crash_base, total_mem; > @@ -541,9 +464,12 @@ static void __init reserve_crashkernel(void) > return; > } > > - if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { > - memblock_free(crash_base, crash_size); > - return; > + if (crash_base >= (1ULL << 32)) { > + if (reserve_crashkernel_low()) { > + memblock_free(crash_base, crash_size); > + return; > + } > + insert_resource(&iomem_resource, &crashk_low_res); > } > > pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n", > diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h > index 525510a9f965..4df8c0bff03e 100644 > --- a/include/linux/crash_core.h > +++ b/include/linux/crash_core.h > @@ -63,6 +63,8 @@ phys_addr_t paddr_vmcoreinfo_note(void); > extern unsigned char *vmcoreinfo_data; > extern size_t vmcoreinfo_size; > extern u32 *vmcoreinfo_note; > +extern struct resource crashk_res; > +extern struct resource crashk_low_res; > > Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, > void *data, size_t data_len); > @@ -74,5 +76,6 @@ int parse_crashkernel_high(char *cmdline, unsigned long long system_ram, > unsigned long long *crash_size, unsigned long long *crash_base); > int parse_crashkernel_low(char *cmdline, unsigned long long system_ram, > unsigned long long *crash_size, unsigned long long *crash_base); > +int __init reserve_crashkernel_low(void); > > #endif /* LINUX_CRASH_CORE_H */ > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > index ea67910ae6b7..a460afdbab0f 100644 > --- a/include/linux/kexec.h > +++ b/include/linux/kexec.h > @@ -330,8 +330,6 @@ extern int kexec_load_disabled; > > /* Location of a reserved region to hold the crash kernel. > */ > -extern struct resource crashk_res; > -extern struct resource crashk_low_res; > extern note_buf_t __percpu *crash_notes; > > /* flag to track if kexec reboot is in progress */ > diff --git a/kernel/crash_core.c b/kernel/crash_core.c > index 9f1557b98468..c81b15dd78c2 100644 > --- a/kernel/crash_core.c > +++ b/kernel/crash_core.c > @@ -7,7 +7,10 @@ > #include <linux/crash_core.h> > #include <linux/utsname.h> > #include <linux/vmalloc.h> > +#include <linux/memblock.h> > +#include <linux/swiotlb.h> > > +#include <asm/kexec.h> > #include <asm/page.h> > #include <asm/sections.h> > > @@ -19,6 +22,22 @@ u32 *vmcoreinfo_note; > /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */ > static unsigned char *vmcoreinfo_data_safecopy; > > +/* Location of the reserved area for the crash kernel */ > +struct resource crashk_res = { > + .name = "Crash kernel", > + .start = 0, > + .end = 0, > + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, > + .desc = IORES_DESC_CRASH_KERNEL > +}; > +struct resource crashk_low_res = { > + .name = "Crash kernel", > + .start = 0, > + .end = 0, > + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, > + .desc = IORES_DESC_CRASH_KERNEL > +}; > + > /* > * parsing the "crashkernel" commandline > * > @@ -292,6 +311,61 @@ int __init parse_crashkernel_low(char *cmdline, > "crashkernel=", suffix_tbl[SUFFIX_LOW]); > } > > +int __init reserve_crashkernel_low(void) > +{ > +#if defined(CONFIG_X86_64) || defined(CONFIG_ARM64) > + unsigned long long base, low_base = 0, low_size = 0; > + unsigned long total_low_mem; > + int ret; > + > + total_low_mem = memblock_mem_size(CRASH_ADDR_LOW_MAX >> PAGE_SHIFT); > + > + /* crashkernel=Y,low */ > + ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, > + &base); > + if (ret) { > + /* > + * two parts from lib/swiotlb.c: > + * -swiotlb size: user-specified with swiotlb= or default. > + * > + * -swiotlb overflow buffer: now hardcoded to 32k. We round it > + * to 8M for other buffers that may need to stay low too. Also > + * make sure we allocate enough extra low memory so that we > + * don't run out of DMA buffers for 32-bit devices. > + */ > + low_size = max(swiotlb_size_or_default() + (8UL << 20), > + 256UL << 20); > + } else { > + /* passed with crashkernel=0,low ? */ > + if (!low_size) > + return 0; > + } > + > + low_base = memblock_find_in_range(0, CRASH_ADDR_LOW_MAX, low_size, CRASH_ALIGN); > + if (!low_base) { > + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", > + (unsigned long)(low_size >> 20)); > + return -ENOMEM; > + } > + > + ret = memblock_reserve(low_base, low_size); > + if (ret) { > + pr_err("%s: Error reserving crashkernel low memblock.\n", > + __func__); > + return ret; > + } > + > + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", > + (unsigned long)(low_size >> 20), > + (unsigned long)(low_base >> 20), > + (unsigned long)(total_low_mem >> 20)); > + > + crashk_low_res.start = low_base; > + crashk_low_res.end = low_base + low_size - 1; > +#endif > + return 0; > +} > + > Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, > void *data, size_t data_len) > { > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > index c19c0dad1ebe..db66bbabfff3 100644 > --- a/kernel/kexec_core.c > +++ b/kernel/kexec_core.c > @@ -53,23 +53,6 @@ note_buf_t __percpu *crash_notes; > /* 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_SYSTEM_RAM, > - .desc = IORES_DESC_CRASH_KERNEL > -}; > -struct resource crashk_low_res = { > - .name = "Crash kernel", > - .start = 0, > - .end = 0, > - .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, > - .desc = IORES_DESC_CRASH_KERNEL > -}; > - > int kexec_should_crash(struct task_struct *p) > { > /* > -- > 2.20.1 > Acked-by: Dave Young <dyoung@redhat.com> Thanks Dave
On Thu, Aug 06, 2020 at 03:36:27PM +0200, Ingo Molnar wrote: > > * Chen Zhou <chenzhou10@huawei.com> wrote: > > > In preparation for supporting reserve_crashkernel_low in arm64 as > > x86_64 does, move reserve_crashkernel_low() into kernel/crash_core.c. > > > > BTW, move x86_64 CRASH_ALIGN to 2M suggested by Dave. CONFIG_PHYSICAL_ALIGN > > can be selected from 2M to 16M, move to the same as arm64. > > > > Signed-off-by: Chen Zhou <chenzhou10@huawei.com> > > --- > > arch/x86/include/asm/kexec.h | 24 ++++++++++ > > arch/x86/kernel/setup.c | 86 +++--------------------------------- > > include/linux/crash_core.h | 3 ++ > > include/linux/kexec.h | 2 - > > kernel/crash_core.c | 74 +++++++++++++++++++++++++++++++ > > kernel/kexec_core.c | 17 ------- > > 6 files changed, 107 insertions(+), 99 deletions(-) > > Since the changes are centered around arm64, I suppose the arm64 tree > will carry this patchset? > > Assuming that this is a 100% invariant moving of code that doesn't > regress on x86: > > Acked-by: Ingo Molnar <mingo@kernel.org> Thanks Ingo. The only difference I see is that CRASH_ALIGN has been reduced to 2M here from 16M for x86. Would this break configs that have PHYSICAL_ALIGN > 2M?
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 6802c59e8252..f8f9d952e09f 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -18,6 +18,30 @@ # define KEXEC_CONTROL_CODE_MAX_SIZE 2048 +/* 2M alignment for crash kernel regions */ +#define CRASH_ALIGN SZ_2M + +/* + * Keep the crash kernel below this limit. + * + * Earlier 32-bits kernels would limit the kernel to the low 512 MB range + * due to mapping restrictions. + * + * 64-bit kdump kernels need to be restricted to be under 64 TB, which is + * the upper limit of system RAM in 4-level paging mode. Since the kdump + * jump could be from 5-level paging to 4-level paging, the jump will fail if + * the kernel is put above 64 TB, and during the 1st kernel bootup there's + * no good way to detect the paging mode of the target kernel which will be + * loaded for dumping. + */ +#ifdef CONFIG_X86_32 +# define CRASH_ADDR_LOW_MAX SZ_512M +# define CRASH_ADDR_HIGH_MAX SZ_512M +#else +# define CRASH_ADDR_LOW_MAX SZ_4G +# define CRASH_ADDR_HIGH_MAX SZ_64T +#endif + #ifndef __ASSEMBLY__ #include <linux/string.h> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index a3767e74c758..46763c1e5d9f 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -401,83 +401,6 @@ static void __init memblock_x86_reserve_range_setup_data(void) #ifdef CONFIG_KEXEC_CORE -/* 16M alignment for crash kernel regions */ -#define CRASH_ALIGN SZ_16M - -/* - * Keep the crash kernel below this limit. - * - * Earlier 32-bits kernels would limit the kernel to the low 512 MB range - * due to mapping restrictions. - * - * 64-bit kdump kernels need to be restricted to be under 64 TB, which is - * the upper limit of system RAM in 4-level paging mode. Since the kdump - * jump could be from 5-level paging to 4-level paging, the jump will fail if - * the kernel is put above 64 TB, and during the 1st kernel bootup there's - * no good way to detect the paging mode of the target kernel which will be - * loaded for dumping. - */ -#ifdef CONFIG_X86_32 -# define CRASH_ADDR_LOW_MAX SZ_512M -# define CRASH_ADDR_HIGH_MAX SZ_512M -#else -# define CRASH_ADDR_LOW_MAX SZ_4G -# define CRASH_ADDR_HIGH_MAX SZ_64T -#endif - -static int __init reserve_crashkernel_low(void) -{ -#ifdef CONFIG_X86_64 - unsigned long long base, low_base = 0, low_size = 0; - unsigned long total_low_mem; - int ret; - - total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT)); - - /* crashkernel=Y,low */ - ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base); - if (ret) { - /* - * two parts from kernel/dma/swiotlb.c: - * -swiotlb size: user-specified with swiotlb= or default. - * - * -swiotlb overflow buffer: now hardcoded to 32k. We round it - * to 8M for other buffers that may need to stay low too. Also - * make sure we allocate enough extra low memory so that we - * don't run out of DMA buffers for 32-bit devices. - */ - low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); - } else { - /* passed with crashkernel=0,low ? */ - if (!low_size) - return 0; - } - - low_base = memblock_find_in_range(0, 1ULL << 32, low_size, CRASH_ALIGN); - if (!low_base) { - pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", - (unsigned long)(low_size >> 20)); - return -ENOMEM; - } - - ret = memblock_reserve(low_base, low_size); - if (ret) { - pr_err("%s: Error reserving crashkernel low memblock.\n", __func__); - return ret; - } - - pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", - (unsigned long)(low_size >> 20), - (unsigned long)(low_base >> 20), - (unsigned long)(total_low_mem >> 20)); - - crashk_low_res.start = low_base; - crashk_low_res.end = low_base + low_size - 1; - insert_resource(&iomem_resource, &crashk_low_res); -#endif - return 0; -} - static void __init reserve_crashkernel(void) { unsigned long long crash_size, crash_base, total_mem; @@ -541,9 +464,12 @@ static void __init reserve_crashkernel(void) return; } - if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { - memblock_free(crash_base, crash_size); - return; + if (crash_base >= (1ULL << 32)) { + if (reserve_crashkernel_low()) { + memblock_free(crash_base, crash_size); + return; + } + insert_resource(&iomem_resource, &crashk_low_res); } pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n", diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h index 525510a9f965..4df8c0bff03e 100644 --- a/include/linux/crash_core.h +++ b/include/linux/crash_core.h @@ -63,6 +63,8 @@ phys_addr_t paddr_vmcoreinfo_note(void); extern unsigned char *vmcoreinfo_data; extern size_t vmcoreinfo_size; extern u32 *vmcoreinfo_note; +extern struct resource crashk_res; +extern struct resource crashk_low_res; Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, void *data, size_t data_len); @@ -74,5 +76,6 @@ int parse_crashkernel_high(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, unsigned long long *crash_base); int parse_crashkernel_low(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, unsigned long long *crash_base); +int __init reserve_crashkernel_low(void); #endif /* LINUX_CRASH_CORE_H */ diff --git a/include/linux/kexec.h b/include/linux/kexec.h index ea67910ae6b7..a460afdbab0f 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -330,8 +330,6 @@ extern int kexec_load_disabled; /* Location of a reserved region to hold the crash kernel. */ -extern struct resource crashk_res; -extern struct resource crashk_low_res; extern note_buf_t __percpu *crash_notes; /* flag to track if kexec reboot is in progress */ diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 9f1557b98468..c81b15dd78c2 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -7,7 +7,10 @@ #include <linux/crash_core.h> #include <linux/utsname.h> #include <linux/vmalloc.h> +#include <linux/memblock.h> +#include <linux/swiotlb.h> +#include <asm/kexec.h> #include <asm/page.h> #include <asm/sections.h> @@ -19,6 +22,22 @@ u32 *vmcoreinfo_note; /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */ static unsigned char *vmcoreinfo_data_safecopy; +/* Location of the reserved area for the crash kernel */ +struct resource crashk_res = { + .name = "Crash kernel", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, + .desc = IORES_DESC_CRASH_KERNEL +}; +struct resource crashk_low_res = { + .name = "Crash kernel", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, + .desc = IORES_DESC_CRASH_KERNEL +}; + /* * parsing the "crashkernel" commandline * @@ -292,6 +311,61 @@ int __init parse_crashkernel_low(char *cmdline, "crashkernel=", suffix_tbl[SUFFIX_LOW]); } +int __init reserve_crashkernel_low(void) +{ +#if defined(CONFIG_X86_64) || defined(CONFIG_ARM64) + unsigned long long base, low_base = 0, low_size = 0; + unsigned long total_low_mem; + int ret; + + total_low_mem = memblock_mem_size(CRASH_ADDR_LOW_MAX >> PAGE_SHIFT); + + /* crashkernel=Y,low */ + ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, + &base); + if (ret) { + /* + * two parts from lib/swiotlb.c: + * -swiotlb size: user-specified with swiotlb= or default. + * + * -swiotlb overflow buffer: now hardcoded to 32k. We round it + * to 8M for other buffers that may need to stay low too. Also + * make sure we allocate enough extra low memory so that we + * don't run out of DMA buffers for 32-bit devices. + */ + low_size = max(swiotlb_size_or_default() + (8UL << 20), + 256UL << 20); + } else { + /* passed with crashkernel=0,low ? */ + if (!low_size) + return 0; + } + + low_base = memblock_find_in_range(0, CRASH_ADDR_LOW_MAX, low_size, CRASH_ALIGN); + if (!low_base) { + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", + (unsigned long)(low_size >> 20)); + return -ENOMEM; + } + + ret = memblock_reserve(low_base, low_size); + if (ret) { + pr_err("%s: Error reserving crashkernel low memblock.\n", + __func__); + return ret; + } + + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", + (unsigned long)(low_size >> 20), + (unsigned long)(low_base >> 20), + (unsigned long)(total_low_mem >> 20)); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; +#endif + return 0; +} + Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, void *data, size_t data_len) { diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index c19c0dad1ebe..db66bbabfff3 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -53,23 +53,6 @@ note_buf_t __percpu *crash_notes; /* 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_SYSTEM_RAM, - .desc = IORES_DESC_CRASH_KERNEL -}; -struct resource crashk_low_res = { - .name = "Crash kernel", - .start = 0, - .end = 0, - .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, - .desc = IORES_DESC_CRASH_KERNEL -}; - int kexec_should_crash(struct task_struct *p) { /*
In preparation for supporting reserve_crashkernel_low in arm64 as x86_64 does, move reserve_crashkernel_low() into kernel/crash_core.c. BTW, move x86_64 CRASH_ALIGN to 2M suggested by Dave. CONFIG_PHYSICAL_ALIGN can be selected from 2M to 16M, move to the same as arm64. Signed-off-by: Chen Zhou <chenzhou10@huawei.com> --- arch/x86/include/asm/kexec.h | 24 ++++++++++ arch/x86/kernel/setup.c | 86 +++--------------------------------- include/linux/crash_core.h | 3 ++ include/linux/kexec.h | 2 - kernel/crash_core.c | 74 +++++++++++++++++++++++++++++++ kernel/kexec_core.c | 17 ------- 6 files changed, 107 insertions(+), 99 deletions(-)