linux-kernel - Re: [GIT PULL] dlm updates for 5.3

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Date:   Wed, 10 Jul 2019 21:05:21 -0700
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     David Teigland <teigland@...hat.com>
Cc:     Linux List Kernel Mailing <linux-kernel@...r.kernel.org>
Subject: Re: [GIT PULL] dlm updates for 5.3

On Tue, Jul 9, 2019 at 9:57 AM David Teigland <teigland@...hat.com> wrote:
>
> Apart from a couple trivial fixes, the more notable fix makes the dlm
> continuing waiting for a user space result if a signal interrupts the
> wait event.

What? No.

That's not sensible at all.

If wait_event_interruptible() returns -ERESTARTSYS, it means that we
have a signal pending.

And if we have a signal pending, then you can't go back and call
wait_event_interruptible() in a loop, because the signal will
*continue* to be pending, so now your "wait event" becomes a kernel
busy loop.

If you don't want to react to signals, then you shouldn't use the
"interruptible()" version of wait-event.

I'm not pulling this. Because the code looks completely and utterly wrong to me.

Am I missing something? Feel free to educate me and re-submit.

               Linus