Commit 4b96b1a1 authored Nov 05, 2006 by Gautham R Shenoy Committed by Linus Torvalds Nov 06, 2006

[PATCH] Fix the spurious unlock_cpu_hotplug false warnings

Cpu-hotplug locking has a minor race case caused because of setting the
variable "recursive" to NULL *after* releasing the cpu_bitmask_lock in the
function unlock_cpu_hotplug,instead of doing so before releasing the
cpu_bitmask_lock.

This was the cause of most of the recent false spurious lock_cpu_unlock
warnings.

This should fix the problem reported by Martin Lorenz reported in
http://lkml.org/lkml/2006/10/29/127

.

Thanks to Srinivasa DS for pointing it out.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent d1ed6a3e

kernel/cpu.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -58,8 +58,8 @@ void unlock_cpu_hotplug(void)
		recursive_depth--;
		return;
		}
		mutex_unlock(&cpu_bitmask_lock);
		recursive = NULL;
		mutex_unlock(&cpu_bitmask_lock);
		}
		EXPORT_SYMBOL_GPL(unlock_cpu_hotplug);

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