diff options
| -rw-r--r-- | arch/i386/kernel/crash.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c index 882779c0787..1bb5dd98d1d 100644 --- a/arch/i386/kernel/crash.c +++ b/arch/i386/kernel/crash.c @@ -30,12 +30,91 @@ typedef u32 note_buf_t[MAX_NOTE_BYTES/4]; note_buf_t crash_notes[NR_CPUS]; +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 = &crash_notes[cpu][0]; + 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_get_current_regs(struct pt_regs *regs) +{ + __asm__ __volatile__("movl %%ebx,%0" : "=m"(regs->ebx)); + __asm__ __volatile__("movl %%ecx,%0" : "=m"(regs->ecx)); + __asm__ __volatile__("movl %%edx,%0" : "=m"(regs->edx)); + __asm__ __volatile__("movl %%esi,%0" : "=m"(regs->esi)); + __asm__ __volatile__("movl %%edi,%0" : "=m"(regs->edi)); + __asm__ __volatile__("movl %%ebp,%0" : "=m"(regs->ebp)); + __asm__ __volatile__("movl %%eax,%0" : "=m"(regs->eax)); + __asm__ __volatile__("movl %%esp,%0" : "=m"(regs->esp)); + __asm__ __volatile__("movw %%ss, %%ax;" :"=a"(regs->xss)); + __asm__ __volatile__("movw %%cs, %%ax;" :"=a"(regs->xcs)); + __asm__ __volatile__("movw %%ds, %%ax;" :"=a"(regs->xds)); + __asm__ __volatile__("movw %%es, %%ax;" :"=a"(regs->xes)); + __asm__ __volatile__("pushfl; popl %0" :"=m"(regs->eflags)); + + regs->eip = (unsigned long)current_text_addr(); +} + +static void crash_save_self(void) +{ + struct pt_regs regs; + int cpu; + cpu = smp_processor_id(); + crash_get_current_regs(®s); + crash_save_this_cpu(®s, cpu); +} + #ifdef CONFIG_SMP static atomic_t waiting_for_crash_ipi; static int crash_nmi_callback(struct pt_regs *regs, int cpu) { local_irq_disable(); + crash_save_this_cpu(regs, cpu); atomic_dec(&waiting_for_crash_ipi); /* Assume hlt works */ __asm__("hlt"); @@ -95,4 +174,5 @@ void machine_crash_shutdown(void) /* The kernel is broken so disable interrupts */ local_irq_disable(); nmi_shootdown_cpus(); + crash_save_self(); } |