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Date:   Thu, 16 Jun 2022 22:51:31 +0900
From:   Dominique Martinet <asmadeus@codewreck.org>
To:     Christian Schoenebeck <linux_oss@crudebyte.com>
Cc:     Eric Van Hensbergen <ericvh@gmail.com>,
        Latchesar Ionkov <lucho@ionkov.net>,
        David Howells <dhowells@redhat.com>,
        linux-fsdevel@vger.kernel.org, stable@vger.kernel.org,
        v9fs-developer@lists.sourceforge.net, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 9p: fix EBADF errors in cached mode
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Christian Schoenebeck wrote on Thu, Jun 16, 2022 at 03:35:59PM +0200:
> 2. I fixed the conflict and gave your patch a test spin, and it triggers
> the BUG_ON(!fid); that you added with that patch. Backtrace based on
> 30306f6194ca ("Merge tag 'hardening-v5.19-rc3' ..."):

hm, that's probably the version I sent without the fallback to
private_data fid if writeback fid was sent (I've only commented without
sending a v2)

> 1. your EBADF patch is based on you recent get/put refactoring patch, so it won't apply on stable.

ugh, you are correct, that was wrong as well in the version I sent by
mail... I've hurried that way too much.

The patch that's currently on the tip of my 9p-next branch should be
alright though, I'll resend it now so you can apply cleanly if you don't
want to fetch https://github.com/martinetd/linux/commits/9p-next

> Did your patch work there for you? I mean I have not applied the other pending
> 9p patches, but they should not really make difference, right? I won't have
> time today, but I will continue to look at it tomorrow. If you already had
> some thoughts on this, that would be great of course.

Yes, my version passes basic tests at least, and I could no longer
reproduce the problem.

Without the if (!fid) fid = file->private_data though it does fail
horribly like you've found out.

--
Dominique