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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 5 Dec 2016 10:25:46 -0800
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Subject: Re: bio linked list corruption.
To: Andy Lutomirski <luto@kernel.org>
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On Mon, Dec 5, 2016 at 10:11 AM, Andy Lutomirski <luto@kernel.org> wrote:
>
> So your kernel has been smp-alternatived.  That 3e comes from
> alternatives_smp_unlock.  If you're running on SMP with UP
> alternatives, things will break.

I'm assuming he's just running in a VM with a single CPU.

The problem that I pointed out with assuming wake_up_all() actually
removes all wait queue entries does not depend on SMP. The race is
much more fundamental and long-lived.

               Linus