From: Brian Foster bfoster@redhat.com
[ Upstream commit 6b789c337a5963ae57cbc7fe9e41488c40a9b014 ]
Prior to commit df732b29c8 ("xfs: call xlog_state_release_iclog with l_icloglock held"), xlog_state_release_iclog() always performed a locked check of the iclog error state before proceeding into the sync state processing code. As of this commit, part of xlog_state_release_iclog() was open-coded into xfs_log_release_iclog() and as a result the locked error state check was lost.
The lockless check still exists, but this doesn't account for the possibility of a race with a shutdown being performed by another task causing the iclog state to change while the original task waits on ->l_icloglock. This has reproduced very rarely via generic/475 and manifests as an assert failure in __xlog_state_release_iclog() due to an unexpected iclog state.
Restore the locked error state check in xlog_state_release_iclog() to ensure that an iclog state update via shutdown doesn't race with the iclog release state processing code.
Fixes: df732b29c807 ("xfs: call xlog_state_release_iclog with l_icloglock held") Reported-by: Zorro Lang zlang@redhat.com Signed-off-by: Brian Foster bfoster@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/xfs/xfs_log.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index f6006d94a581e..796ff37d5bb5b 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -605,18 +605,23 @@ xfs_log_release_iclog( struct xlog *log = mp->m_log; bool sync;
- if (iclog->ic_state == XLOG_STATE_IOERROR) { - xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); - return -EIO; - } + if (iclog->ic_state == XLOG_STATE_IOERROR) + goto error;
if (atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) { + if (iclog->ic_state == XLOG_STATE_IOERROR) { + spin_unlock(&log->l_icloglock); + goto error; + } sync = __xlog_state_release_iclog(log, iclog); spin_unlock(&log->l_icloglock); if (sync) xlog_sync(log, iclog); } return 0; +error: + xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); + return -EIO; }
/*