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@xxxxxxxxxx> --- fs/xfs/xfs_inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index f643a9295179..4591598ca04d 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -3614,7 +3614,6 @@ xfs_iflush_cluster( * 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 @@ xfs_iflush_cluster( * 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); -- 2.17.2
