Re: [PATCH v2 2/2] ext4: check return value of blkdev_issue_flush() when starting a fast commit

[sashiko-bot@kernel.org]

> When the file system device differs from the journal device, a cache
> flush is issued on the file system device before fast commit blocks
> are written, but the return value is ignored.  If the cache flush
> fails, the fast commit blocks are written and the fast commit
> completes anyway, even though the updates covered by the preceding
> transactions may not be on stable storage yet, so the fast commit may
> provide guarantees it cannot keep.
> 
> Check the return value of blkdev_issue_flush() and abort the fast
> commit if the cache flush fails.  ext4_fc_commit() will then fall back
> to a full journal commit, so the caller still gets the expected
> durability guarantees.
> 
> Since a cache flush failure now aborts the fast commit, also issue
> the flush only when the journal barrier option is enabled, consistent
> with the file system device flush issued during a full journal commit
> and with the fast commit tail block flush.  This keeps file systems
> mounted with nobarrier working on devices with failing cache flushes.
> 
> Fixes: da0c5d2695265 ("ext4: issue fsdev cache flush before starting fast commit")
> Cc: stable@vger.kernel.org
> Signed-off-by: guolingxing <guolingxing@tju.edu.cn>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20261013082331.2089623-1-guolingxing@tju.edu.cn?part=2