48 lines
1.8 KiB
Diff
48 lines
1.8 KiB
Diff
From 6c18fde82cd02e550fb0c095bd6c6908dcc77747 Mon Sep 17 00:00:00 2001
|
|
From: Brian Foster <bfoster@redhat.com>
|
|
Date: Thu, 28 Apr 2022 15:39:03 -0400
|
|
Subject: [PATCH] xfs: terminate perag iteration reliably on agcount
|
|
|
|
Source kernel commit: 8ed004eb9d07a5d6114db3e97a166707c186262d
|
|
|
|
The for_each_perag_from() iteration macro relies on sb_agcount to
|
|
process every perag currently within EOFS from a given starting
|
|
point. It's perfectly valid to have perag structures beyond
|
|
sb_agcount, however, such as if a growfs is in progress. If a perag
|
|
loop happens to race with growfs in this manner, it will actually
|
|
attempt to process the post-EOFS perag where ->pag_agno ==
|
|
sb_agcount. This is reproduced by xfs/104 and manifests as the
|
|
following assert failure in superblock write verifier context:
|
|
|
|
XFS: Assertion failed: agno < mp->m_sb.sb_agcount, file: fs/xfs/libxfs/xfs_types.c, line: 22
|
|
|
|
Update the corresponding macro to only process perags that are
|
|
within the current sb_agcount.
|
|
|
|
Fixes: 58d43a7e3263 ("xfs: pass perags around in fsmap data dev functions")
|
|
Signed-off-by: Brian Foster <bfoster@redhat.com>
|
|
Reviewed-by: Dave Chinner <dchinner@redhat.com>
|
|
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
|
|
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
|
|
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
|
|
---
|
|
libxfs/xfs_ag.h | 2 +-
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
|
|
|
diff --git a/libxfs/xfs_ag.h b/libxfs/xfs_ag.h
|
|
index 9cd0669..fae2a38 100644
|
|
--- a/libxfs/xfs_ag.h
|
|
+++ b/libxfs/xfs_ag.h
|
|
@@ -144,7 +144,7 @@ xfs_perag_next(
|
|
(pag) = xfs_perag_next((pag), &(agno)))
|
|
|
|
#define for_each_perag_from(mp, agno, pag) \
|
|
- for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount, (pag))
|
|
+ for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
|
|
|
|
|
|
#define for_each_perag(mp, agno, pag) \
|
|
--
|
|
1.8.3.1
|
|
|