Merge branch 'linus' into percpu-cpumask-x86-for-linus-2

[safe/jmp/linux-2.6] / arch / x86 / kernel / crash.c

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index fb298d1..ff95824 100644 (file)
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -24,20 +24,13 @@
 #include <asm/apic.h>
 #include <asm/hpet.h>
 #include <linux/kdebug.h>
-#include <asm/smp.h>
+#include <asm/cpu.h>
 #include <asm/reboot.h>
-
-#include <mach_ipi.h>
+#include <asm/virtext.h>
 
 
 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
 
-/* This keeps a track of which one is crashing cpu. */
-static int crashing_cpu;
-static nmi_shootdown_cb shootdown_callback;
-
-static atomic_t waiting_for_crash_ipi;
-
 static void kdump_nmi_callback(int cpu, struct die_args *args)
 {
        struct pt_regs *regs;
@@ -55,77 +48,16 @@ static void kdump_nmi_callback(int cpu, struct die_args *args)
 #endif
        crash_save_cpu(regs, cpu);
 
-       disable_local_APIC();
-}
-
-static int crash_nmi_callback(struct notifier_block *self,
-                       unsigned long val, void *data)
-{
-       int cpu;
-
-       if (val != DIE_NMI_IPI)
-               return NOTIFY_OK;
-
-       cpu = raw_smp_processor_id();
-
-       /* Don't do anything if this handler is invoked on crashing cpu.
-        * Otherwise, system will completely hang. Crashing cpu can get
-        * an NMI if system was initially booted with nmi_watchdog parameter.
-        */
-       if (cpu == crashing_cpu)
-               return NOTIFY_STOP;
-       local_irq_disable();
-
-       shootdown_callback(cpu, (struct die_args *)data);
-
-       atomic_dec(&waiting_for_crash_ipi);
-       /* Assume hlt works */
-       halt();
-       for (;;)
-               cpu_relax();
-
-       return 1;
-}
-
-static void smp_send_nmi_allbutself(void)
-{
-       cpumask_t mask = cpu_online_map;
-       cpu_clear(safe_smp_processor_id(), mask);
-       if (!cpus_empty(mask))
-               send_IPI_mask(mask, NMI_VECTOR);
-}
-
-static struct notifier_block crash_nmi_nb = {
-       .notifier_call = crash_nmi_callback,
-};
-
-void nmi_shootdown_cpus(nmi_shootdown_cb callback)
-{
-       unsigned long msecs;
-
-       /* Make a note of crashing cpu. Will be used in NMI callback.*/
-       crashing_cpu = safe_smp_processor_id();
-
-       shootdown_callback = callback;
-
-       atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
-       /* Would it be better to replace the trap vector here? */
-       if (register_die_notifier(&crash_nmi_nb))
-               return;         /* return what? */
-       /* Ensure the new callback function is set before sending
-        * out the NMI
+       /* Disable VMX or SVM if needed.
+        *
+        * We need to disable virtualization on all CPUs.
+        * Having VMX or SVM enabled on any CPU may break rebooting
+        * after the kdump kernel has finished its task.
         */
-       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--;
-       }
+       cpu_emergency_vmxoff();
+       cpu_emergency_svm_disable();
 
-       /* Leave the nmi callback set */
+       disable_local_APIC();
 }
 
 static void kdump_nmi_shootdown_cpus(void)
@@ -156,6 +88,14 @@ void native_machine_crash_shutdown(struct pt_regs *regs)
        local_irq_disable();
 
        kdump_nmi_shootdown_cpus();
+
+       /* Booting kdump kernel with VMX or SVM enabled won't work,
+        * because (among other limitations) we can't disable paging
+        * with the virt flags.
+        */
+       cpu_emergency_vmxoff();
+       cpu_emergency_svm_disable();
+
        lapic_shutdown();
 #if defined(CONFIG_X86_IO_APIC)
        disable_IO_APIC();