This is a note to let you know that I've just added the patch titled
btrfs: convert BUG_ON in btrfs_reloc_cow_block() to proper error handling
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-convert-bug_on-in-btrfs_reloc_cow_block-to-pro.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fa178eed11f3532e28d6f3d4e522efe5ee495d50
Author: Josef Bacik <josef@xxxxxxxxxxxxxx>
Date: Thu Oct 3 11:43:03 2024 -0400
btrfs: convert BUG_ON in btrfs_reloc_cow_block() to proper error handling
[ Upstream commit 6a4730b325aaa48f7a5d5ba97aff0a955e2d9cec ]
This BUG_ON is meant to catch backref cache problems, but these can
arise from either bugs in the backref cache or corruption in the extent
tree. Fix it to be a proper error.
Reviewed-by: Boris Burkov <boris@xxxxxx>
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 89ad7e12c08bb..062154c6a65f6 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4789,8 +4789,18 @@ int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
WARN_ON(!first_cow && level == 0);
node = rc->backref_cache.path[level];
- BUG_ON(node->bytenr != buf->start &&
- node->new_bytenr != buf->start);
+
+ /*
+ * If node->bytenr != buf->start and node->new_bytenr !=
+ * buf->start then we've got the wrong backref node for what we
+ * expected to see here and the cache is incorrect.
+ */
+ if (unlikely(node->bytenr != buf->start && node->new_bytenr != buf->start)) {
+ btrfs_err(fs_info,
+"bytenr %llu was found but our backref cache was expecting %llu or %llu",
+ buf->start, node->bytenr, node->new_bytenr);
+ return -EUCLEAN;
+ }
drop_node_buffer(node);
extent_buffer_get(cow);
