commit 4b827b3f305d ("xfs: remove WARN when dquot cache insertion fails")

Disk quota cache insertion failure doesn't require this warning as
the system can still manage and track disk quotas without caching the
dquot object into memory. The failure doesn't imply any data loss or
corruption.

Therefore, the WARN_ON in xfs_qm_dqget_cache_insert function is aggressive
and causes bot noise. I have confirmed there are no conflicts and also
tested the using the C repro from syzkaller:
https://syzkaller.appspot.com/text?tag=ReproC&x=15406772280000

Please do let me know if I missed out on anything as it's my first
backport patch.

Reported-by: syzbot+55fb1b7d909494fd520d@syzkaller.appspotmail.com
Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
---
 fs/xfs/xfs_dquot.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index 8fb90da89787..7f071757f278 100644
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -798,7 +798,6 @@ xfs_qm_dqget_cache_insert(
 	error = radix_tree_insert(tree, id, dqp);
 	if (unlikely(error)) {
 		/* Duplicate found!  Caller must try again. */
-		WARN_ON(error != -EEXIST);
 		mutex_unlock(&qi->qi_tree_lock);
 		trace_xfs_dqget_dup(dqp);
 		return error;
-- 
2.34.1

On Fri, Aug 09, 2024 at 07:26:40AM +0530, Abhinav Jain wrote:
> commit 4b827b3f305d ("xfs: remove WARN when dquot cache insertion fails")
> 
> Disk quota cache insertion failure doesn't require this warning as
> the system can still manage and track disk quotas without caching the
> dquot object into memory. The failure doesn't imply any data loss or
> corruption.
> 
> Therefore, the WARN_ON in xfs_qm_dqget_cache_insert function is aggressive
> and causes bot noise. I have confirmed there are no conflicts and also
> tested the using the C repro from syzkaller:
> https://syzkaller.appspot.com/text?tag=ReproC&x=15406772280000
> 
> Please do let me know if I missed out on anything as it's my first
> backport patch.

You lost all of the ownership and original signed-off-by attributes for
the commit :(

Please work with the xfs developers if they wish to see this backported
or not, that's up to them.

thanks,

greg k-h

On Mon, 12 Aug 2024 16:40:13 +0200, Greg K-H wrote:
> You lost all of the ownership and original signed-off-by attributes for
> the commit :(
>

I will work on this to understand how to avoid such mistake moving forward.

> Please work with the xfs developers if they wish to see this backported
> or not, that's up to them.
>
> thanks,
> 
> greg k-h

I am tagging XFS maintainers so that they can confirm the same. If there
is a go ahead, only then I will submit a v2 retaining the original
signed-off-by attributes.

Thanks,
Abhinav
---

Hi Abhinav,

Thanks for your message! Fixing bot noise from WARNs isn't a high
priority for me for patches to backport to stable, but I'm currently
working on a set anyways so I'll throw this patch in. No need to
resend anything.

- Leah

On Mon, Aug 12, 2024 at 12:51 PM Abhinav Jain <jain.abhinav177@gmail.com> wrote:
>
> On Mon, 12 Aug 2024 16:40:13 +0200, Greg K-H wrote:
> > You lost all of the ownership and original signed-off-by attributes for
> > the commit :(
> >
>
> I will work on this to understand how to avoid such mistake moving forward.
>
> > Please work with the xfs developers if they wish to see this backported
> > or not, that's up to them.
> >
> > thanks,
> >
> > greg k-h
>
> I am tagging XFS maintainers so that they can confirm the same. If there
> is a go ahead, only then I will submit a v2 retaining the original
> signed-off-by attributes.
>
> Thanks,
> Abhinav
> ---