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Date:   Mon, 27 Jun 2022 15:27:03 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     linux-kernel@vger.kernel.org, mingo@redhat.com,
        ebiederm@xmission.com,
        Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= <toke@redhat.com>,
        Kalle Valo <kvalo@kernel.org>,
        Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [PATCH] signal: break out of wait loops on kthread_stop()
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On Mon, Jun 27, 2022 at 02:00:20PM +0200, Jason A. Donenfeld wrote:

> +bool __kthread_should_stop(struct task_struct *k)
> +{
> +	return (k->flags & PF_KTHREAD) &&
> +	       test_bit(KTHREAD_SHOULD_STOP, &to_kthread(k)->flags);
> +}

This used to be a racy pattern; not sure it still is since Eric poked at
this last, but please use __to_kthread() instead.