x86 kdump: extract kdump-specific code from crash_nmi_callback()

Impact: cleanup

The NMI CPU-halting code will be used on non-kdump cases, also
(e.g. emergency_reboot when virtualization is enabled).

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 20 insertions, 11 deletions

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 268553817909..60475422a51a 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -35,19 +35,34 @@ static int crashing_cpu;
 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
 static atomic_t waiting_for_crash_ipi;
 
-static int crash_nmi_callback(struct notifier_block *self,
-                        unsigned long val, void *data)
+static void kdump_nmi_callback(int cpu, struct die_args *args)
 {
         struct pt_regs *regs;
 #ifdef CONFIG_X86_32
         struct pt_regs fixed_regs;
 #endif
+
+        regs = args->regs;
+
+#ifdef CONFIG_X86_32
+        if (!user_mode_vm(regs)) {
+                crash_fixup_ss_esp(&fixed_regs, regs);
+                regs = &fixed_regs;
+        }
+#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;
 
-        regs = ((struct die_args *)data)->regs;
         cpu = raw_smp_processor_id();
 
         /* Don't do anything if this handler is invoked on crashing cpu.
@@ -58,14 +73,8 @@ static int crash_nmi_callback(struct notifier_block *self,
                 return NOTIFY_STOP;
         local_irq_disable();
 
-#ifdef CONFIG_X86_32
-        if (!user_mode_vm(regs)) {
-                crash_fixup_ss_esp(&fixed_regs, regs);
-                regs = &fixed_regs;
-        }
-#endif
-        crash_save_cpu(regs, cpu);
-        disable_local_APIC();
+        kdump_nmi_callback(cpu, (struct die_args *)data);
+
         atomic_dec(&waiting_for_crash_ipi);
         /* Assume hlt works */
         halt();