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-rw-r--r--arch/i386/kernel/crash.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c
index fa27a6c2abb..882779c0787 100644
--- a/arch/i386/kernel/crash.c
+++ b/arch/i386/kernel/crash.c
@@ -23,12 +23,65 @@
#include <asm/hardirq.h>
#include <asm/nmi.h>
#include <asm/hw_irq.h>
+#include <mach_ipi.h>
#define MAX_NOTE_BYTES 1024
typedef u32 note_buf_t[MAX_NOTE_BYTES/4];
note_buf_t crash_notes[NR_CPUS];
+#ifdef CONFIG_SMP
+static atomic_t waiting_for_crash_ipi;
+
+static int crash_nmi_callback(struct pt_regs *regs, int cpu)
+{
+ local_irq_disable();
+ atomic_dec(&waiting_for_crash_ipi);
+ /* Assume hlt works */
+ __asm__("hlt");
+ for(;;);
+ return 1;
+}
+
+/*
+ * By using the NMI code instead of a vector we just sneak thru the
+ * word generator coming out with just what we want. AND it does
+ * not matter if clustered_apic_mode is set or not.
+ */
+static void smp_send_nmi_allbutself(void)
+{
+ send_IPI_allbutself(APIC_DM_NMI);
+}
+
+static void nmi_shootdown_cpus(void)
+{
+ unsigned long msecs;
+ atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+
+ /* Would it be better to replace the trap vector here? */
+ set_nmi_callback(crash_nmi_callback);
+ /* Ensure the new callback function is set before sending
+ * out the NMI
+ */
+ wmb();
+
+ smp_send_nmi_allbutself();
+
+ msecs = 1000; /* Wait at most a second for the other cpus to stop */
+ while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
+ mdelay(1);
+ msecs--;
+ }
+
+ /* Leave the nmi callback set */
+}
+#else
+static void nmi_shootdown_cpus(void)
+{
+ /* There are no cpus to shootdown */
+}
+#endif
+
void machine_crash_shutdown(void)
{
/* This function is only called after the system
@@ -39,4 +92,7 @@ void machine_crash_shutdown(void)
* In practice this means shooting down the other cpus in
* an SMP system.
*/
+ /* The kernel is broken so disable interrupts */
+ local_irq_disable();
+ nmi_shootdown_cpus();
}