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xfs: shutdown after buf release in iflush cluster abort path

If xfs_iflush_cluster() fails due to corruption, the error path
issues a shutdown and simulates an I/O completion to release the
buffer. This code has a couple small problems. First, the shutdown
sequence can issue a synchronous log force, which is unsafe to do
with buffer locks held. Second, the simulated I/O completion does not
guarantee the buffer is async and thus is unlocked and released.

For example, if the last operation on the buffer was a read off disk
prior to the corruption event, XBF_ASYNC is not set and the buffer
is left locked and held upon return. This results in a memory leak
as shown by the following message on module unload:

 BUG xfs_buf (...): Objects remaining in xfs_buf on __kmem_cache_shutdown()

Fix both of these problems by setting XBF_ASYNC on the buffer prior
to the simulated I/O error and performing the shutdown immediately
after ioend processing when the buffer has been released.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
hifive-unleashed-5.2
Brian Foster 2019-04-12 07:39:20 -07:00 committed by Darrick J. Wong
parent 545aa41f5c
commit 22fedd80b6
1 changed files with 3 additions and 1 deletions

View File

@ -3614,7 +3614,6 @@ cluster_corrupt_out:
* inode buffer and shut down the filesystem.
*/
rcu_read_unlock();
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
/*
* We'll always have an inode attached to the buffer for completion
@ -3624,11 +3623,14 @@ cluster_corrupt_out:
* xfs_buf_submit().
*/
ASSERT(bp->b_iodone);
bp->b_flags |= XBF_ASYNC;
bp->b_flags &= ~XBF_DONE;
xfs_buf_stale(bp);
xfs_buf_ioerror(bp, -EIO);
xfs_buf_ioend(bp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
/* abort the corrupt inode, as it was not attached to the buffer */
xfs_iflush_abort(cip, false);
kmem_free(cilist);