From 4b96b1a10cb00c867103b21f0f2a6c91b705db11 Mon Sep 17 00:00:00 2001 From: Gautham R Shenoy Date: Sun, 5 Nov 2006 23:52:04 -0800 Subject: [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/cpu.c') diff --git a/kernel/cpu.c b/kernel/cpu.c index 663c920b2234..272254f20d97 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -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); -- cgit v1.2.3 From 112cecb2cc0e7341db92281ba04b26c41bb8146d Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Wed, 6 Dec 2006 20:34:31 -0800 Subject: [PATCH] suspend: don't change cpus_allowed for task initiating the suspend Don't modify the cpus_allowed of the task initiating the suspend. _cpu_down() already makes sure that the task doing the suspend doesn't run on dying cpu. Signed-off-by: Suresh Siddha Cc: Venkatesh Pallipadi Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Nigel Cunningham Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/cpu.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel/cpu.c') diff --git a/kernel/cpu.c b/kernel/cpu.c index 272254f20d97..9124669f4586 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -270,11 +270,7 @@ int disable_nonboot_cpus(void) goto out; } } - error = set_cpus_allowed(current, cpumask_of_cpu(first_cpu)); - if (error) { - printk(KERN_ERR "Could not run on CPU%d\n", first_cpu); - goto out; - } + /* We take down all of the non-boot CPUs in one shot to avoid races * with the userspace trying to use the CPU hotplug at the same time */ -- cgit v1.2.3