[patch 02/10] idle: Fix machine check handling in idle loop.

From: Martin Schwidefsky
Date: Wed Mar 05 2008 - 06:57:56 EST


From: Heiko Carstens <heiko.carstens@xxxxxxxxxx>

If a machine check handling is pending when the idle loop is entered
default_idle will be left with timer ticks and virtual timer disabled.
Fix this by "calling" the idle_chain. Also a BUG_ON(!in_interrupt) in
start_hz_timer must be removed since the function now gets called from
non interrupt context as well.

Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---

arch/s390/kernel/process.c | 4 ++++
arch/s390/kernel/time.c | 2 --
2 files changed, 4 insertions(+), 2 deletions(-)

Index: quilt-2.6/arch/s390/kernel/process.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/process.c
+++ quilt-2.6/arch/s390/kernel/process.c
@@ -152,6 +152,10 @@ static void default_idle(void)
local_mcck_disable();
if (test_thread_flag(TIF_MCCK_PENDING)) {
local_mcck_enable();
+ /* disable monitor call class 0 */
+ __ctl_clear_bit(8, 15);
+ atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
+ hcpu);
local_irq_enable();
s390_handle_mcck();
return;
Index: quilt-2.6/arch/s390/kernel/time.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/time.c
+++ quilt-2.6/arch/s390/kernel/time.c
@@ -209,8 +209,6 @@ static void stop_hz_timer(void)
*/
static void start_hz_timer(void)
{
- BUG_ON(!in_interrupt());
-
if (!cpu_isset(smp_processor_id(), nohz_cpu_mask))
return;
account_ticks(get_clock());

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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