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* [BUGFIX] cpufreq: dont BUG_ON uninitialized policy cpu
@ 2010-01-13  5:14 Wu Fengguang
  2010-01-13  6:32 ` Dave Jones
  2010-01-13 12:42 ` Thomas Renninger
  0 siblings, 2 replies; 6+ messages in thread
From: Wu Fengguang @ 2010-01-13  5:14 UTC (permalink / raw)
  To: Dave Jones; +Cc: Thomas Renninger, LKML

Remove a BUG_ON which is always triggered here after commit 0b19a310eebb93:

[    6.879063] kernel BUG at drivers/cpufreq/cpufreq.c:88!
[    6.879381] invalid opcode: 0000 [#1] SMP
[    6.879711] last sysfs file:
[    6.879918] CPU 3
[    6.880114] Pid: 1, comm: swapper Not tainted 2.6.33-rc3-next-20100112 #51 DX58SO/
[    6.880611] RIP: 0010:[<ffffffff81577729>]  [<ffffffff81577729>] lock_policy_rwsem_write+0x69/0x90
...
[    6.885630] Process swapper (pid: 1, threadinfo ffff8800bbbdc000, task ffff8800bbbe0000)
...
[    6.888135] Call Trace:
[    6.888318]  [<ffffffff8157851a>] cpufreq_update_policy+0x2a/0x110
...
[    6.892586]  [<ffffffff81c981e6>] cpufreq_stats_init+0x83/0xb5

CC: Thomas Renninger <trenn@suse.de>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
 drivers/cpufreq/cpufreq.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- linux-mm.orig/drivers/cpufreq/cpufreq.c	2010-01-13 13:06:03.000000000 +0800
+++ linux-mm/drivers/cpufreq/cpufreq.c	2010-01-13 13:06:57.000000000 +0800
@@ -72,7 +72,8 @@ int lock_policy_rwsem_##mode						\
 (int cpu)								\
 {									\
 	int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu);		\
-	BUG_ON(policy_cpu == -1);					\
+	if (policy_cpu == -1)						\
+		return -1;						\
 	down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu));		\
 	if (unlikely(!cpu_online(cpu))) {				\
 		up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu));	\

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2010-01-14  2:42 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-01-13  5:14 [BUGFIX] cpufreq: dont BUG_ON uninitialized policy cpu Wu Fengguang
2010-01-13  6:32 ` Dave Jones
2010-01-13 12:42 ` Thomas Renninger
2010-01-13 12:48   ` Wu Fengguang
2010-01-13 15:59   ` Dave Jones
2010-01-14  2:42     ` Wu Fengguang

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