Make the functions reserve_crashkernel[_low]() as generic. Arm64 will use these to reimplement crashkernel=X. Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx> Tested-by: John Donnelly <John.p.donnelly@xxxxxxxxxx> --- arch/x86/include/asm/kexec.h | 25 ++++++ arch/x86/kernel/setup.c | 151 +------------------------------- include/linux/crash_core.h | 4 + include/linux/kexec.h | 2 - kernel/crash_core.c | 164 +++++++++++++++++++++++++++++++++++ kernel/kexec_core.c | 17 ---- 6 files changed, 195 insertions(+), 168 deletions(-) diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 8cf9d3fd31c7..34afa7b645f9 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -21,6 +21,27 @@ /* 2M 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 + #ifndef __ASSEMBLY__ #include <linux/string.h> @@ -200,6 +221,10 @@ typedef void crash_vmclear_fn(void); extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss; extern void kdump_nmi_shootdown_cpus(void); +#ifdef CONFIG_KEXEC_CORE +extern void __init reserve_crashkernel(void); +#endif + #endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_KEXEC_H */ diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 1289f079ad5f..00b3840d30f9 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -25,8 +25,6 @@ #include <uapi/linux/mount.h> -#include <xen/xen.h> - #include <asm/apic.h> #include <asm/numa.h> #include <asm/bios_ebda.h> @@ -38,6 +36,7 @@ #include <asm/io_apic.h> #include <asm/kasan.h> #include <asm/kaslr.h> +#include <asm/kexec.h> #include <asm/mce.h> #include <asm/mtrr.h> #include <asm/realmode.h> @@ -389,153 +388,7 @@ static void __init memblock_x86_reserve_range_setup_data(void) } } -/* - * --------- Crashkernel reservation ------------------------------ - */ - -#ifdef CONFIG_KEXEC_CORE - -/* - * 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 low_mem_limit; - int ret; - - low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX); - - /* crashkernel=Y,low */ - ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &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_phys_alloc_range(low_size, CRASH_ALIGN, CRASH_ALIGN, CRASH_ADDR_LOW_MAX); - if (!low_base) { - pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", - (unsigned long)(low_size >> 20)); - return -ENOMEM; - } - - pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n", - (unsigned long)(low_size >> 20), - (unsigned long)(low_base >> 20), - (unsigned long)(low_mem_limit >> 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; - bool high = false; - int ret; - - total_mem = memblock_phys_mem_size(); - - /* crashkernel=XM */ - ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base); - if (ret != 0 || crash_size <= 0) { - /* crashkernel=X,high */ - ret = parse_crashkernel_high(boot_command_line, total_mem, - &crash_size, &crash_base); - if (ret != 0 || crash_size <= 0) - return; - high = true; - } - - if (xen_pv_domain()) { - pr_info("Ignoring crashkernel for a Xen PV domain\n"); - return; - } - - /* 0 means: find the address automatically */ - if (!crash_base) { - /* - * Set CRASH_ADDR_LOW_MAX upper bound for crash memory, - * crashkernel=x,high reserves memory over CRASH_ADDR_LOW_MAX, - * also allocates 256M extra low memory for DMA buffers - * and swiotlb. - * But the extra memory is not required for all machines. - * So try low memory first and fall back to high memory - * unless "crashkernel=size[KMG],high" is specified. - */ - if (!high) - crash_base = memblock_phys_alloc_range(crash_size, - CRASH_ALIGN, CRASH_ALIGN, - CRASH_ADDR_LOW_MAX); - if (!crash_base) - crash_base = memblock_phys_alloc_range(crash_size, - CRASH_ALIGN, CRASH_ALIGN, - CRASH_ADDR_HIGH_MAX); - if (!crash_base) { - pr_info("crashkernel reservation failed - No suitable area found.\n"); - return; - } - } else { - unsigned long long start; - - start = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base, - crash_base + crash_size); - if (start != crash_base) { - pr_info("crashkernel reservation failed - memory is in use.\n"); - return; - } - } - - if (crash_base >= CRASH_ADDR_LOW_MAX && reserve_crashkernel_low()) { - memblock_free(crash_base, crash_size); - return; - } - - pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n", - (unsigned long)(crash_size >> 20), - (unsigned long)(crash_base >> 20), - (unsigned long)(total_mem >> 20)); - - crashk_res.start = crash_base; - crashk_res.end = crash_base + crash_size - 1; - insert_resource(&iomem_resource, &crashk_res); -} -#else +#ifndef CONFIG_KEXEC_CORE static void __init reserve_crashkernel(void) { } diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h index 206bde8308b2..5021d7c70aee 100644 --- a/include/linux/crash_core.h +++ b/include/linux/crash_core.h @@ -69,6 +69,9 @@ 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; + /* raw contents of kernel .notes section */ extern const void __start_notes __weak; extern const void __stop_notes __weak; @@ -83,5 +86,6 @@ 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 9e93bef52968..f301f2f5cfc4 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -337,8 +337,6 @@ 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 106e4500fd53..d39892bdb9ae 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -7,7 +7,12 @@ #include <linux/crash_core.h> #include <linux/utsname.h> #include <linux/vmalloc.h> +#include <linux/memblock.h> +#include <linux/swiotlb.h> +#include <xen/xen.h> + +#include <asm/kexec.h> #include <asm/page.h> #include <asm/sections.h> @@ -21,6 +26,22 @@ 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 * @@ -294,6 +315,149 @@ int __init parse_crashkernel_low(char *cmdline, "crashkernel=", suffix_tbl[SUFFIX_LOW]); } +/* + * --------- Crashkernel reservation ------------------------------ + */ + +int __init reserve_crashkernel_low(void) +{ +#ifdef CONFIG_X86_64 + unsigned long long base, low_base = 0, low_size = 0; + unsigned long low_mem_limit; + int ret; + + low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX); + + /* crashkernel=Y,low */ + ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &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_phys_alloc_range(low_size, CRASH_ALIGN, CRASH_ALIGN, + CRASH_ADDR_LOW_MAX); + if (!low_base) { + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", + (unsigned long)(low_size >> 20)); + return -ENOMEM; + } + + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n", + (unsigned long)(low_size >> 20), + (unsigned long)(low_base >> 20), + (unsigned long)(low_mem_limit >> 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; +} + +#ifdef CONFIG_X86 +#ifdef CONFIG_KEXEC_CORE +/* + * reserve_crashkernel() - reserves memory for crash kernel + * + * This function reserves memory area given in "crashkernel=" kernel command + * line parameter. The memory reserved is used by dump capture kernel when + * primary kernel is crashing. + */ +void __init reserve_crashkernel(void) +{ + unsigned long long crash_size, crash_base, total_mem; + bool high = false; + int ret; + + total_mem = memblock_phys_mem_size(); + + /* crashkernel=XM */ + ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base); + if (ret != 0 || crash_size <= 0) { + /* crashkernel=X,high */ + ret = parse_crashkernel_high(boot_command_line, total_mem, + &crash_size, &crash_base); + if (ret != 0 || crash_size <= 0) + return; + high = true; + } + + if (xen_pv_domain()) { + pr_info("Ignoring crashkernel for a Xen PV domain\n"); + return; + } + + /* 0 means: find the address automatically */ + if (!crash_base) { + /* + * Set CRASH_ADDR_LOW_MAX upper bound for crash memory, + * crashkernel=x,high reserves memory over CRASH_ADDR_LOW_MAX, + * also allocates 256M extra low memory for DMA buffers + * and swiotlb. + * But the extra memory is not required for all machines. + * So try low memory first and fall back to high memory + * unless "crashkernel=size[KMG],high" is specified. + */ + if (!high) + crash_base = memblock_phys_alloc_range(crash_size, + CRASH_ALIGN, CRASH_ALIGN, + CRASH_ADDR_LOW_MAX); + if (!crash_base) + crash_base = memblock_phys_alloc_range(crash_size, + CRASH_ALIGN, CRASH_ALIGN, + CRASH_ADDR_HIGH_MAX); + if (!crash_base) { + pr_info("crashkernel reservation failed - No suitable area found.\n"); + return; + } + } else { + /* User specifies base address explicitly. */ + unsigned long long start; + + if (!IS_ALIGNED(crash_base, CRASH_ALIGN)) { + pr_warn("cannot reserve crashkernel: base address is not %ldMB aligned\n", + (unsigned long)CRASH_ALIGN >> 20); + return; + } + + start = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base, + crash_base + crash_size); + if (start != crash_base) { + pr_info("crashkernel reservation failed - memory is in use.\n"); + return; + } + } + + if (crash_base >= CRASH_ADDR_LOW_MAX && reserve_crashkernel_low()) { + memblock_free(crash_base, crash_size); + return; + } + + pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n", + (unsigned long)(crash_size >> 20), + (unsigned long)(crash_base >> 20), + (unsigned long)(total_mem >> 20)); + + crashk_res.start = crash_base; + crashk_res.end = crash_base + crash_size - 1; + insert_resource(&iomem_resource, &crashk_res); +} +#endif /* CONFIG_KEXEC_CORE */ +#endif + 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 8798a8183974..2ca887514145 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 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec