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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Sun, 14 Aug 2022 10:57:48 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>, x86-ml <x86@kernel.org>
Subject: Re: [GIT PULL] timer fixes
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> I think the issue is that "current->sighand" is always safe (and that 
> "me->sighand" is the same thing), and that sighand has RCU-delayed 
> freeing so that __lock_task_sighand() can safely try to take the lock of 
> another process' sighand.

Yeah - 'me' (== current) here can never go away from under the locking 
context which is 'me' as well.

Thanks,

	Ingo