stop_machine() now uses hard_irq_disable

Add a call to hard_irq_disable() to stop_machine so that we make sure IRQs are
really disabled and not only lazy-disabled on archs like powerpc as some users
of stop_machine() may rely on that.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index daabb74ee0bc..fcee2a8e6da3 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -8,6 +8,8 @@
 #include <linux/sched.h>
 #include <linux/stop_machine.h>
 #include <linux/syscalls.h>
+#include <linux/interrupt.h>
+
 #include <asm/atomic.h>
 #include <asm/semaphore.h>
 #include <asm/uaccess.h>
@@ -45,6 +47,7 @@ static int stopmachine(void *cpu)
                 if (stopmachine_state == STOPMACHINE_DISABLE_IRQ 
                     && !irqs_disabled) {
                         local_irq_disable();
+                        hard_irq_disable();
                         irqs_disabled = 1;
                         /* Ack: irqs disabled. */
                         smp_mb(); /* Must read state first. */
@@ -124,6 +127,7 @@ static int stop_machine(void)
 
         /* Make them disable irqs. */
         local_irq_disable();
+        hard_irq_disable();
         stopmachine_set_state(STOPMACHINE_DISABLE_IRQ);
 
         return 0;