[PATCH] cpu hotplug/x86_64: disable interrupt in play_dead
With physical CPU hotplug, the CPU is hot removed and it should not receive
any interrupts. Disabling interrupt is much safer. This basically is what we
do in ia64 & x86.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c
index 7519fc5..3060ed9 100644
--- a/arch/x86_64/kernel/process.c
+++ b/arch/x86_64/kernel/process.c
@@ -157,7 +157,7 @@
DECLARE_PER_CPU(int, cpu_state);
#include <asm/nmi.h>
-/* We don't actually take CPU down, just spin without interrupts. */
+/* We halt the CPU with physical CPU hotplug */
static inline void play_dead(void)
{
idle_task_exit();
@@ -166,8 +166,9 @@
/* Ack it */
__get_cpu_var(cpu_state) = CPU_DEAD;
+ local_irq_disable();
while (1)
- safe_halt();
+ halt();
}
#else
static inline void play_dead(void)