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-rw-r--r--arch/i386/kernel/crash.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c
index 882779c..1bb5dd9 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, &note, 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, &note, 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(&regs);
+ crash_save_this_cpu(&regs, 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();
}