From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Cox <alan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Subject: Re: [PATCH v2] firmware: fix sending -ERESTARTSYS due to signal on
 fallback
Date: Tue, 06 Jun 2017 15:53:16 +0100
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> "Unix tradition (and thus almost all applications) believe file store
> writes to
> be non signal interruptible. It would not be safe or practical to
> change that
> guarantee."

Yep everyone codes

	write(disk_file, "foo", 3);

not while(..) blah around it.

> For these two reasons then it would seem best we do two things
> actually:
> 
> 1) return -EINTR instead of -EAGAIN when we detect
> swait_event_interruptible_timeout()
> got interrupted by a signal (it returns -ERESTARTSYS)
> 2) Do as you note below and add wait_event_killable_timeout()

Pedantic detail that I don't think affects you

If you have completed a part of the I/O then you should return the byte
processed count not EINTR, but -1,EINTR if no progress was made.

Alan