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Date:   Wed, 11 Mar 2020 12:01:50 +0100
From:   =?utf-8?Q?Ond=C5=99ej?= Jirman <megi@xff.cz>
To:     Chao Yu <yuchao0@huawei.com>
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Subject: Re: [f2fs-dev] Writes stoped working on f2fs after the compression
 support was added
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On Wed, Mar 11, 2020 at 06:51:23PM +0800, Chao Yu wrote:
> Hi,
> 
> >> Oops, it looks previous fix patch just cover the root cause... :(
> >>
> >> Did this issue still happen frequently? If it is, would you please apply patch
> >> that prints log during down/up semaphore.
> > 
> > Not frequently. Just once. I couldn't afford FS corruption during update,
> 
> Alright.
> 
> > so I reverted the compression support shortly after.
> 
> What I can see is that filesystem was just stuck, rather than image became
> corrupted, I guess the condition is not such bad, anyway, it's okay to just
> revert compression support for now to keep fs stable.

Yes, to be precise, file writes were not completed and fs was stuck.
The system as a whole would probably become unbootable if this would
happen to core libraries necessary for systemd, or something like that,
but filesystem itself was not corrupted.

Re-writing the files was enough to recover the system.

I guess we'll see if there will be more reports after 5.6 is released,
or if it's just some quirk in my system.

I'll try to collect more information, once I'll have some time, to
get to the bottom of this.

thank you and regards,
	o.