From fd59d231f81cb02870b9cf15f456a897f3669b4e Mon Sep 17 00:00:00 2001 From: Ken'ichi Ohmichi Date: Tue, 16 Oct 2007 23:27:27 -0700 Subject: [PATCH] Add vmcoreinfo This patch set frees the restriction that makedumpfile users should install a vmlinux file (including the debugging information) into each system. makedumpfile command is the dump filtering feature for kdump. It creates a small dumpfile by filtering unnecessary pages for the analysis. To distinguish unnecessary pages, it needs a vmlinux file including the debugging information. These days, the debugging package becomes a huge file, and it is hard to install it into each system. To solve the problem, kdump developers discussed it at lkml and kexec-ml. As the result, we reached the conclusion that necessary information for dump filtering (called "vmcoreinfo") should be embedded into the first kernel file and it should be accessed through /proc/vmcore during the second kernel. (http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.0/1806.html) Dan Aloni created the patch set for the above implementation. (http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.1/1053.html) And I updated it for multi architectures and memory models. (http://lists.infradead.org/pipermail/kexec/2007-August/000479.html) Signed-off-by: Dan Aloni Signed-off-by: Ken'ichi Ohmichi Signed-off-by: Bernhard Walle Signed-off-by: Daisuke Nishimura Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/kernel/machine_kexec.c | 30 ++++++++ arch/ia64/mm/discontig.c | 2 +- arch/x86/kernel/machine_kexec_32.c | 13 ++++ arch/x86/kernel/machine_kexec_64.c | 9 +++ include/asm-ia64/numa.h | 1 + include/linux/kexec.h | 26 +++++++ kernel/kexec.c | 110 +++++++++++++++++++++++++++++ kernel/ksysfs.c | 10 +++ 8 files changed, 200 insertions(+), 1 deletion(-) diff --git a/arch/ia64/kernel/machine_kexec.c b/arch/ia64/kernel/machine_kexec.c index 58e943a5d95..40f9c3e1922 100644 --- a/arch/ia64/kernel/machine_kexec.c +++ b/arch/ia64/kernel/machine_kexec.c @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include #include #include @@ -121,3 +123,31 @@ void machine_kexec(struct kimage *image) unw_init_running(ia64_machine_kexec, image); for(;;); } + +void arch_crash_save_vmcoreinfo(void) +{ +#ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE + SYMBOL(pgdat_list); + LENGTH(pgdat_list, MAX_NUMNODES); + + SYMBOL(node_memblk); + LENGTH(node_memblk, NR_NODE_MEMBLKS); + SIZE(node_memblk_s); + OFFSET(node_memblk_s, start_paddr); + OFFSET(node_memblk_s, size); +#endif +#ifdef CONFIG_PGTABLE_3 + CONFIG(PGTABLE_3); +#elif CONFIG_PGTABLE_4 + CONFIG(PGTABLE_4); +#endif +} + +unsigned long paddr_vmcoreinfo_note(void) +{ + unsigned long vaddr, paddr; + vaddr = (unsigned long)(char *)&vmcoreinfo_note; + asm volatile ("tpa %0 = %1" : "=r"(paddr) : "r"(vaddr) : "memory"); + return paddr; +} + diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index 5628067a74d..0b567398f38 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -48,7 +48,7 @@ struct early_node_data { static struct early_node_data mem_data[MAX_NUMNODES] __initdata; static nodemask_t memory_less_mask __initdata; -static pg_data_t *pgdat_list[MAX_NUMNODES]; +pg_data_t *pgdat_list[MAX_NUMNODES]; /* * To prevent cache aliasing effects, align per-node structures so that they diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c index deda9a221cf..ae20fa5afa6 100644 --- a/arch/x86/kernel/machine_kexec_32.c +++ b/arch/x86/kernel/machine_kexec_32.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -169,3 +170,15 @@ static int __init parse_crashkernel(char *arg) return 0; } early_param("crashkernel", parse_crashkernel); + +void arch_crash_save_vmcoreinfo(void) +{ +#ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE + SYMBOL(node_data); + LENGTH(node_data, MAX_NUMNODES); +#endif +#ifdef CONFIG_X86_PAE + CONFIG(X86_PAE); +#endif +} + diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index cd1899a2f0c..e333ea110a5 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -257,3 +258,11 @@ static int __init setup_crashkernel(char *arg) } early_param("crashkernel", setup_crashkernel); +void arch_crash_save_vmcoreinfo(void) +{ +#ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE + SYMBOL(node_data); + LENGTH(node_data, MAX_NUMNODES); +#endif +} + diff --git a/include/asm-ia64/numa.h b/include/asm-ia64/numa.h index 7d5e2ccc37a..6a8a27cfae3 100644 --- a/include/asm-ia64/numa.h +++ b/include/asm-ia64/numa.h @@ -24,6 +24,7 @@ extern u16 cpu_to_node_map[NR_CPUS] __cacheline_aligned; extern cpumask_t node_to_cpu_mask[MAX_NUMNODES] __cacheline_aligned; +extern pg_data_t *pgdat_list[MAX_NUMNODES]; /* Stuff below this line could be architecture independent */ diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 8c2c7fcd58c..99f2d6f0c83 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -121,6 +121,23 @@ extern struct page *kimage_alloc_control_pages(struct kimage *image, extern void crash_kexec(struct pt_regs *); int kexec_should_crash(struct task_struct *); void crash_save_cpu(struct pt_regs *regs, int cpu); +void crash_save_vmcoreinfo(void); +void arch_crash_save_vmcoreinfo(void); +void vmcoreinfo_append_str(const char *fmt, ...); +unsigned long paddr_vmcoreinfo_note(void); + +#define SYMBOL(name) \ + vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name) +#define SIZE(name) \ + vmcoreinfo_append_str("SIZE(%s)=%d\n", #name, sizeof(struct name)) +#define OFFSET(name, field) \ + vmcoreinfo_append_str("OFFSET(%s.%s)=%d\n", #name, #field, \ + &(((struct name *)0)->field)) +#define LENGTH(name, value) \ + vmcoreinfo_append_str("LENGTH(%s)=%d\n", #name, value) +#define CONFIG(name) \ + vmcoreinfo_append_str("CONFIG_%s=y\n", #name) + extern struct kimage *kexec_image; extern struct kimage *kexec_crash_image; @@ -148,11 +165,20 @@ extern struct kimage *kexec_crash_image; #define KEXEC_FLAGS (KEXEC_ON_CRASH) /* List of defined/legal kexec flags */ +#define VMCOREINFO_BYTES (4096) +#define VMCOREINFO_NOTE_NAME "VMCOREINFO" +#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4) +#define VMCOREINFO_NOTE_SIZE (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \ + + VMCOREINFO_NOTE_NAME_BYTES) + /* Location of a reserved region to hold the crash kernel. */ extern struct resource crashk_res; typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4]; extern note_buf_t *crash_notes; +extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; +extern unsigned int vmcoreinfo_size; +extern unsigned int vmcoreinfo_max_size; #else /* !CONFIG_KEXEC */ diff --git a/kernel/kexec.c b/kernel/kexec.c index d8de12e943c..67828befbfc 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -21,16 +21,26 @@ #include #include #include +#include +#include +#include #include #include #include #include #include +#include /* Per cpu memory for storing cpu states in case of system crash. */ note_buf_t* crash_notes; +/* vmcoreinfo stuff */ +unsigned char vmcoreinfo_data[VMCOREINFO_BYTES]; +u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; +unsigned int vmcoreinfo_size = 0; +unsigned int vmcoreinfo_max_size = sizeof(vmcoreinfo_data); + /* Location of the reserved area for the crash kernel */ struct resource crashk_res = { .name = "Crash kernel", @@ -1060,6 +1070,7 @@ void crash_kexec(struct pt_regs *regs) 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); } @@ -1134,3 +1145,102 @@ static int __init crash_notes_memory_init(void) return 0; } module_init(crash_notes_memory_init) + +void crash_save_vmcoreinfo(void) +{ + u32 *buf; + + if (!vmcoreinfo_size) + return; + + vmcoreinfo_append_str("CRASHTIME=%d", xtime.tv_sec); + + buf = (u32 *)vmcoreinfo_note; + + buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, + vmcoreinfo_size); + + final_note(buf); +} + +void vmcoreinfo_append_str(const char *fmt, ...) +{ + va_list args; + char buf[0x50]; + int r; + + va_start(args, fmt); + r = vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + + if (r + vmcoreinfo_size > vmcoreinfo_max_size) + 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 __attribute__ ((weak)) arch_crash_save_vmcoreinfo(void) +{} + +unsigned long __attribute__ ((weak)) paddr_vmcoreinfo_note(void) +{ + return __pa((unsigned long)(char *)&vmcoreinfo_note); +} + +static int __init crash_save_vmcoreinfo_init(void) +{ + vmcoreinfo_append_str("OSRELEASE=%s\n", UTS_RELEASE); + vmcoreinfo_append_str("PAGESIZE=%d\n", PAGE_SIZE); + + SYMBOL(init_uts_ns); + SYMBOL(node_online_map); + SYMBOL(swapper_pg_dir); + SYMBOL(_stext); + +#ifndef CONFIG_NEED_MULTIPLE_NODES + SYMBOL(mem_map); + SYMBOL(contig_page_data); +#endif +#ifdef CONFIG_SPARSEMEM + SYMBOL(mem_section); + LENGTH(mem_section, NR_SECTION_ROOTS); + SIZE(mem_section); + OFFSET(mem_section, section_mem_map); +#endif + SIZE(page); + SIZE(pglist_data); + SIZE(zone); + SIZE(free_area); + SIZE(list_head); + OFFSET(page, flags); + OFFSET(page, _count); + OFFSET(page, mapping); + OFFSET(page, lru); + OFFSET(pglist_data, node_zones); + OFFSET(pglist_data, nr_zones); +#ifdef CONFIG_FLAT_NODE_MEM_MAP + OFFSET(pglist_data, node_mem_map); +#endif + OFFSET(pglist_data, node_start_pfn); + OFFSET(pglist_data, node_spanned_pages); + OFFSET(pglist_data, node_id); + OFFSET(zone, free_area); + OFFSET(zone, vm_stat); + OFFSET(zone, spanned_pages); + OFFSET(free_area, free_list); + OFFSET(list_head, next); + OFFSET(list_head, prev); + LENGTH(zone.free_area, MAX_ORDER); + + arch_crash_save_vmcoreinfo(); + + return 0; +} + +module_init(crash_save_vmcoreinfo_init) diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 6046939d080..38b38f957ef 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -61,6 +61,15 @@ static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page) return sprintf(page, "%d\n", !!kexec_crash_image); } KERNEL_ATTR_RO(kexec_crash_loaded); + +static ssize_t vmcoreinfo_show(struct kset *kset, char *page) +{ + return sprintf(page, "%lx %x\n", + paddr_vmcoreinfo_note(), + vmcoreinfo_max_size); +} +KERNEL_ATTR_RO(vmcoreinfo); + #endif /* CONFIG_KEXEC */ /* @@ -96,6 +105,7 @@ static struct attribute * kernel_attrs[] = { #ifdef CONFIG_KEXEC &kexec_loaded_attr.attr, &kexec_crash_loaded_attr.attr, + &vmcoreinfo_attr.attr, #endif NULL }; -- 2.41.1