diff options
Diffstat (limited to 'arch/x86_64/kernel/crash.c')
| -rw-r--r-- | arch/x86_64/kernel/crash.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c index abc601f..4e6c3b7 100644 --- a/arch/x86_64/kernel/crash.c +++ b/arch/x86_64/kernel/crash.c @@ -11,9 +11,12 @@ #include <linux/types.h> #include <linux/kernel.h> #include <linux/smp.h> +#include <linux/irq.h> #include <linux/reboot.h> #include <linux/kexec.h> #include <linux/delay.h> +#include <linux/elf.h> +#include <linux/elfcore.h> #include <asm/processor.h> #include <asm/hardirq.h> @@ -24,6 +27,71 @@ /* This keeps a track of which one is crashing cpu. */ static int crashing_cpu; +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)); +} + +static void crash_save_this_cpu(struct pt_regs *regs, int cpu) +{ + struct elf_prstatus prstatus; + u32 *buf; + + if ((cpu < 0) || (cpu >= NR_CPUS)) + 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 that 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_regs(&prstatus.pr_reg, regs); + buf = append_elf_note(buf, "CORE", NT_PRSTATUS, &prstatus, + sizeof(prstatus)); + final_note(buf); +} + +static void crash_save_self(struct pt_regs *regs) +{ + int cpu; + + cpu = smp_processor_id(); + crash_save_this_cpu(regs, cpu); +} + #ifdef CONFIG_SMP static atomic_t waiting_for_crash_ipi; @@ -38,6 +106,7 @@ static int crash_nmi_callback(struct pt_regs *regs, int cpu) return 1; local_irq_disable(); + crash_save_this_cpu(regs, cpu); disable_local_APIC(); atomic_dec(&waiting_for_crash_ipi); /* Assume hlt works */ @@ -113,4 +182,5 @@ void machine_crash_shutdown(struct pt_regs *regs) disable_IO_APIC(); #endif + crash_save_self(regs); } |