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Date:   Thu, 14 Apr 2022 14:08:32 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     rjw@rjwysocki.net, mingo@kernel.org, vincent.guittot@linaro.org,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de,
        ebiederm@xmission.com, bigeasy@linutronix.de,
        Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
        tj@kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH 2/5] sched,ptrace: Fix ptrace_check_attach() vs PREEMPT_RT
Message-ID: <20220414120831.GB32752@redhat.com>
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this doesn't really matter, just for completeness:

On 04/14, Oleg Nesterov wrote:
>
> 	if (wait_on_bit(&task->jobctl, JOBCTL_TRACED_XXX_BIT, TASK_KILLABLE))
> 		return -EINTR;
>
> this is fine,

No, this is wrong too. wake_up_bit() does exclusive wakeup.

Oleg.