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-rw-r--r--arch/x86_64/kernel/crash.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c
index abc601f36b6..4e6c3b729e3 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, &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 = (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);
}