Re: Question about LTS 4.19 patch "89047634f5ce NFS: Don't interrupt file writeout due to fatal errors"

[Trond Myklebust]

On Mon, 2023-10-30 at 17:04 +0800, ChenXiaoSong wrote:
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> On 2023/10/30 16:58, Greg KH wrote:
> > If you just revert that one patch, is the issue resolved?  And what
> > about other stable releases that have that change in it?
> > 
> > If this does need to be reverted, please submit a patch that does
> > so and
> > we can review it that way.
> > 
> > thanks,
> > 
> > greg k-h
> 
> 
> In my opinion, this patch is not for fixing a bug, but is part of a
> refactoring patchset. The 'Fixes:' tag should not be added.
> 
> 

A refactoring is by definition a change that does not affect code
behaviour. It is obvious that this was never intended to be such a
patch.

The reason that the bug is occurring in 4.19.x, and not in the latest
kernels, is because the former is missing another bugfix (one which
actually is missing a "Fixes:" tag).

Can you therefore please check if applying commit 22876f540bdf ("NFS:
Don't call generic_error_remove_page() while holding locks") fixes the
issue.

Note that the latter patch is needed in any case in order to fix a read
deadlock (as indicated on the label).

Thanks,
  Trond

-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx