[PATCH] i386: Use safe_apic_wait_icr_idle in safe_apic_wait_icr_idle …

…- i386

Use safe_apic_wait_icr_idle to check ICR idle bit if the vector is
NMI_VECTOR to avoid potential hangups in the event of crash when kdump
tries to stop the other CPUs.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>

arch/i386/kernel/smp.c

@@ -175,7 +175,10 @@ static inline void __send_IPI_dest_field(unsigned long mask, int vector)
 	/*
 	 * Wait for idle.
 	 */
-	apic_wait_icr_idle();
+	if (unlikely(vector == NMI_VECTOR))
+		safe_apic_wait_icr_idle();
+	else
+		apic_wait_icr_idle();
 
 	/*
 	 * prepare target chip field