From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Gruenbacher <agruenba@redhat.com>
Date: Tue, 31 Aug 2021 17:01:48 +0200
Subject: [Cluster-devel] [bug report] new ->follow_link() and
 ->put_link() calling conventions
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References: <20210831100729.GA16317@kili>
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Hi Dan,

On Tue, Aug 31, 2021 at 12:15 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> Hello GFS2 devs,
>
> The ancient patch 680baacbca69: "new ->follow_link() and ->put_link()
> calling conventions" from May 2, 2015, leads to the following
> Smatch static checker warning:
>
>         fs/gfs2/inode.c:1806 gfs2_get_link()
>         error: passing non negative 13 to ERR_PTR

this looks like a false positive: gh->gh_error will only be set to
GLR_TRYFAILED when try_futile is true, and try_futile will only be
true when the LM_FLAG_TRY or LM_FLAG_TRY_1CB flag in gh->gh_flags is
set. The code is a bit convoluted, and it's not surprising that smatch
doesn't understand what's going on.

Thanks,
Andreas