From 0b89c0a733912937edb7565f19337b3bce2b4783 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Wed, 22 Jan 2020 11:29:46 -0500 Subject: [PATCH] xfs: don't check for AG deadlock for realtime files in bunmapi Source kernel commit: 69ffe5960df16938bccfe1b65382af0b3de51265 Commit 5b094d6dac04 ("xfs: fix multi-AG deadlock in xfs_bunmapi") added a check in __xfs_bunmapi() to stop early if we would touch multiple AGs in the wrong order. However, this check isn't applicable for realtime files. In most cases, it just makes us do unnecessary commits. However, without the fix from the previous commit ("xfs: fix realtime file data space leak"), if the last and second-to-last extents also happen to have different "AG numbers", then the break actually causes __xfs_bunmapi() to return without making any progress, which sends xfs_itruncate_extents_flags() into an infinite loop. Fixes: 5b094d6dac04 ("xfs: fix multi-AG deadlock in xfs_bunmapi") Signed-off-by: Omar Sandoval Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Signed-off-by: Eric Sandeen --- libxfs/xfs_bmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c index f961f8aa4..f68216880 100644 --- a/libxfs/xfs_bmap.c +++ b/libxfs/xfs_bmap.c @@ -5396,7 +5396,7 @@ __xfs_bunmapi( * Make sure we don't touch multiple AGF headers out of order * in a single transaction, as that could cause AB-BA deadlocks. */ - if (!wasdel) { + if (!wasdel && !isrt) { agno = XFS_FSB_TO_AGNO(mp, del.br_startblock); if (prev_agno != NULLAGNUMBER && prev_agno > agno) break; -- 2.50.1