[PATCH] x86_64 irq_regs fix

smp_apic_timer_interrupt() needs to stack the pt_regs* for profile_tick.

If any other of those APIC interrupt handlers want to run get_irq_regs() then
their C entrypoint handlers will need the same treatment.

Cc: Andi Kleen <[e-mail]>
Cc: David Howells <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Acked-by: Andrew Vasquez <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/x86_64/kernel/apic.c

···
  * [ if a single-CPU system runs an SMP kernel then we call the local
  *   interrupt as well. Thus we cannot inline the local irq ... ]
  */
-void smp_apic_timer_interrupt(void)
+void smp_apic_timer_interrupt(struct pt_regs *regs)
 {
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
 	/*
 	 * the NMI deadlock-detector uses this.
 	 */
···
 	irq_enter();
 	smp_local_timer_interrupt();
 	irq_exit();
+	set_irq_regs(old_regs);
 }
 
 /*