commit 44d9b07e52db25035680713c3428016cadcd2ea1 upstream.
Committing a transaction tx0 with a defer ops chain of (A, B, C)
creates a chain of transactions that looks like this:
tx0 -> txA -> txB -> txC
Prior to commit cb042117488dbf, __xfs_trans_commit would run precommits
on tx0, then call xfs_defer_finish_noroll to convert A-C to tx[A-C].
Unfortunately, after the finish_noroll loop we forgot to run precommits
on txC. That was fixed by adding the second precommit call.
Unfortunately, none of us remembered that xfs_defer_finish_noroll
calls __xfs_trans_commit a second time to commit tx0 before finishing
work A in txA and committing that. In other words, we run precommits
twice on tx0:
xfs_trans_commit(tx0)
__xfs_trans_commit(tx0, false)
xfs_trans_run_precommits(tx0)
xfs_defer_finish_noroll(tx0)
xfs_trans_roll(tx0)
txA = xfs_trans_dup(tx0)
__xfs_trans_commit(tx0, true)
xfs_trans_run_precommits(tx0)
This currently isn't an issue because the inode item precommit is
idempotent; the iunlink item precommit deletes itself so it can't be
called again; and the buffer/dquot item precommits only check the incore
objects for corruption. However, it doesn't make sense to run
precommits twice.
Fix this situation by only running precommits after finish_noroll.
Cc: <stable@vger.kernel.org> # v6.4
Fixes: cb042117488dbf ("xfs: defered work could create precommits")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ccab6aad13