[PATCH 4.4 51/53] xfs: fix unaligned access in xfs_btree_visit_blocks

Greg Kroah-Hartman
2017-06-05T17:19:53Z

From: Eric Sandeen <sandeen@sandeen.net>

commit a4d768e702de224cc85e0c8eac9311763403b368 upstream.

This structure copy was throwing unaligned access warnings on sparc64:

Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs]

xfs_btree_copy_ptrs does a memcpy, which avoids it.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/xfs/libxfs/xfs_btree.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -4064,7 +4064,7 @@ xfs_btree_change_owner(
xfs_btree_readahead_ptr(cur, ptr, 1);

/* save for the next iteration of the loop */
- lptr = *ptr;
+ xfs_btree_copy_ptrs(cur, &lptr, ptr, 1);
}

/* for each buffer in the level */