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From:   "Theodore Ts'o" <tytso@mit.edu>
To:     enwlinux@gmail.com, linux-ext4@vger.kernel.org
Cc:     "Theodore Ts'o" <tytso@mit.edu>, yebin10@huawei.com
Subject: Re: [PATCH] ext4: fix extent status tree race in writeback error recovery path
Date:   Thu, 14 Jul 2022 10:57:52 -0400
Message-Id: <165781065440.2470585.17226618557732749649.b4-ty@mit.edu>
In-Reply-To: <20220615160530.1928801-1-enwlinux@gmail.com>
References: <20220615160530.1928801-1-enwlinux@gmail.com>
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On Wed, 15 Jun 2022 12:05:30 -0400, Eric Whitney wrote:
> A race can occur in the unlikely event ext4 is unable to allocate a
> physical cluster for a delayed allocation in a bigalloc file system
> during writeback.  Failure to allocate a cluster forces error recovery
> that includes a call to mpage_release_unused_pages().  That function
> removes any corresponding delayed allocated blocks from the extent
> status tree.  If a new delayed write is in progress on the same cluster
> simultaneously, resulting in the addition of an new extent containing
> one or more blocks in that cluster to the extent status tree, delayed
> block accounting can be thrown off if that delayed write then encounters
> a similar cluster allocation failure during future writeback.
> 
> [...]

Applied, thanks!

[1/1] ext4: fix extent status tree race in writeback error recovery path
      commit: 8e469e57340049d4735b71660d29bd4fd3ae1607

Best regards,
-- 
Theodore Ts'o <tytso@mit.edu>