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From:   Daire Byrne <daire@dneg.com>
Date:   Tue, 22 Nov 2022 08:00:02 +0000
Message-ID: <CAPt2mGOaLQh2v-Bk8rLni3jXx+rwy9uNOudg+kc-P2pWEJ6QbA@mail.gmail.com>
Subject: Re: [PATCH 0/1] Fix oops in cachefiles_prepare_write due to
 cookie_lru and use_cookie race
To:     Dave Wysochanski <dwysocha@redhat.com>
Cc:     David Howells <dhowells@redhat.com>,
        Daire Byrne <daire.byrne@gmail.com>,
        Benjamin Maynard <benmaynard@google.com>,
        linux-cachefs@redhat.com, linux-nfs@vger.kernel.org
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On Thu, 17 Nov 2022 at 11:52, Dave Wysochanski <dwysocha@redhat.com> wrote:
>
> This patch should fix the oops seen by Daire while testing the latest
> NFS netfs fscache conversion patches [1][2].  What follows is a detailed
> explanation of the analysis, mostly for reference and in case any of
> the patch header is unclear.

I can now confirm that this does indeed fix the issue I was hitting -
it has been over 4 days and I have not seen the crash that I was
reliably reproducing at least once a day.

Many thanks for tracking this down Dave.

I will try to switch over to the v2 patch sometime this week but I
don't expect a change in functionality. The important thing is you
found the place where it was going wrong and why.

Tested-by: Daire Byrne <daire@dneg.com>

Daire