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Sender: Tejun Heo <htejun@gmail.com>
Date: Wed, 17 Apr 2024 15:55:57 -1000
From: Tejun Heo <tj@kernel.org>
To: Sven Schnelle <svens@linux.ibm.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] workqueue: fix selection of wake_cpu in kick_pool()
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Hello,

On Wed, Apr 17, 2024 at 05:36:38PM +0200, Sven Schnelle wrote:
> > This generally seems like a good idea but isn't this still racy? The CPU may
> > go down between setting p->wake_cpu and wake_up_process().
> 
> Don't know without reading the source, but how does this code normally
> protect against that?

Probably by wrapping determining the wake_cpu and the wake_up inside
cpu_read_lock() section.

Thanks.

-- 
tejun