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Date:   Mon, 25 Sep 2023 12:08:14 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Ming Qian <ming.qian@nxp.com>
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Subject: Re: [PATCH] wait: don't wake up freezable wait by freezing fake
 signal
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On Tue, Aug 22, 2023 at 03:45:47PM +0800, Ming Qian wrote:
> kernel may try to wake up task with fake signal when freezing task,
> if the task is waiting event using wait_event_freezable,
> it's better to freeze the wait, instead of breaking it.
> 
> otherwise the caller may need to retry the wait,
> maybe like below code:
> 
> 	if (rc == -ERESTARTSYS && freezing(current)) {
> 		clear_thread_flag(TIF_SIGPENDING);
> 		goto again;
> 	}

I'm not sure I get it -- is there an actual problem, or are you trying
to optimize something?