[PATCH 5.10 CANDIDATE 5/9] xfs: force the log offline when log intent item recovery fails

[Amir Goldstein <amir73il@gmail.com>]

From: "Darrick J. Wong" <djwong@kernel.org>

commit 4e6b8270c820c8c57a73f869799a0af2b56eff3e upstream.

If any part of log intent item recovery fails, we should shut down the
log immediately to stop the log from writing a clean unmount record to
disk, because the metadata is not consistent.  The inability to cancel a
dirty transaction catches most of these cases, but there are a few
things that have slipped through the cracks, such as ENOSPC from a
transaction allocation, or runtime errors that result in cancellation of
a non-dirty transaction.

This solves some weird behaviors reported by customers where a system
goes down, the first mount fails, the second succeeds, but then the fs
goes down later because of inconsistent metadata.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 fs/xfs/xfs_log.c         | 3 +++
 fs/xfs/xfs_log_recover.c | 5 ++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 05791456adbb..22d7d74231d4 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -765,6 +765,9 @@ xfs_log_mount_finish(
 	if (readonly)
 		mp->m_flags |= XFS_MOUNT_RDONLY;
 
+	/* Make sure the log is dead if we're returning failure. */
+	ASSERT(!error || (mp->m_log->l_flags & XLOG_IO_ERROR));
+
 	return error;
 }
 
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 87886b7f77da..69408782019e 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -2457,8 +2457,10 @@ xlog_finish_defer_ops(
 
 		error = xfs_trans_alloc(mp, &resv, dfc->dfc_blkres,
 				dfc->dfc_rtxres, XFS_TRANS_RESERVE, &tp);
-		if (error)
+		if (error) {
+			xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);
 			return error;
+		}
 
 		/*
 		 * Transfer to this new transaction all the dfops we captured
@@ -3454,6 +3456,7 @@ xlog_recover_finish(
 			 * this) before we get around to xfs_log_mount_cancel.
 			 */
 			xlog_recover_cancel_intents(log);
+			xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
 			xfs_alert(log->l_mp, "Failed to recover intents");
 			return error;
 		}
-- 
2.25.1