Re: [PATCH 01/21] workqueue: fix race condition in schedule_on_each_cpu()

Frederic Weisbecker
2009-11-16T23:04:40Z

On Tue, Nov 17, 2009 at 02:15:06AM +0900, Tejun Heo wrote:
> Commit 65a64464349883891e21e74af16c05d6e1eeb4e9 which allows
> schedule_on_each_cpu() to be called from keventd added a race
> condition. schedule_on_each_cpu() may race with cpu hotplug and end
> up executing the function twice on a cpu.
>
> Fix it by moving direct execution into the section protected with
> get/put_online_cpus(). While at it, update code such that direct
> execution is done after works have been scheduled for all other cpus
> and drop unnecessary cpu != orig test from flush loop.
>
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Cc: Andi Kleen <ak@linux.intel.com>
> Cc: Oleg Nesterov <oleg@redhat.com>
> ---

Shouldn't this patch go to .32 ?
This looks like an important fix.