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Date: Mon, 4 Mar 2024 12:31:45 +0100
From: Greg KH <greg@kroah.com>
To: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org,
	Trond Myklebust <trond.myklebust@hammerspace.com>,
	Anna Schumaker <anna@kernel.org>, linux-nfs@vger.kernel.org,
	Jacek Tomaka <Jacek.Tomaka@poczta.fm>
Subject: Re: [PATCH stable 6.1] NFS: Fix data corruption caused by congestion.
Message-ID: <2024030439-exclusion-tanning-b1d9@gregkh>
References: <170907634991.24797.14120500624611379941@noble.neil.brown.name>
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On Wed, Feb 28, 2024 at 10:25:49AM +1100, NeilBrown wrote:
> 
> when AOP_WRITEPAGE_ACTIVATE is returned (as NFS does when it detects
> congestion) it is important that the page is redirtied.
> nfs_writepage_locked() doesn't do this, so files can become corrupted as
> writes can be lost.
> 
> Note that this is not needed in v6.8 as AOP_WRITEPAGE_ACTIVATE cannot be
> returned.  It is needed for kernels v5.18..v6.7.  From 6.3 onward the patch
> is different as it needs to mention "folio", not "page".
> 
> Reported-and-tested-by: Jacek Tomaka <Jacek.Tomaka@poczta.fm>
> Fixes: 6df25e58532b ("nfs: remove reliance on bdi congestion")
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>  fs/nfs/write.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

All now queued up, thanks.

greg k-h