Hi,

On 2021-02-19 04:17, Wang Yugui wrote:

quoted

Hi, Josef Bacik

We noticed an error in 5.10.x backport of 'btrfs: fix possible free
space tree corruption with online conversion'

It is wrong in 5.10.13, but right in 5.11.

5.10.13

@@ -146,6 +146,9 @@ enum {
  	BTRFS_FS_STATE_DEV_REPLACING,
  	/* The btrfs_fs_info created for self-tests */
  	BTRFS_FS_STATE_DUMMY_FS_INFO,
+
+	/* Indicate that we can't trust the free space tree for caching yet */
+	BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
  };

the usage sample of this enum:
set_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);


5.11
enum{
..
     /* Indicate that the discard workqueue can service discards. */
     BTRFS_FS_DISCARD_RUNNING,

     /* Indicate that we need to cleanup space cache v1 */
     BTRFS_FS_CLEANUP_SPACE_CACHE_V1,

     /* Indicate that we can't trust the free space tree for caching yet */
     BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
};

the usage sample of this enum:
set_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);

Out of curiosity I decided to check how this happened, but don't see it.
Here is the commit that went into 5.10.13 and it looks correct to me:

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=2175bf57dc9522c58d93dcd474758434a3f05c57

The patch that went into 5.10 looks identical to the original commit in 5.11.
What tree are you looking at?

the 5.10.y is the URL that you point out.

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=2175bf57dc9522c58d93dcd474758434a3f05c57

but the right one for 5.11 is
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/btrfs?id=2f96e40212d435b328459ba6b3956395eed8fa9f

5.11:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/btrfs?id=2f96e40212d435b328459ba6b3956395eed8fa9f

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0225c5208f44c..47ca8edafb5e6 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h

@@ -564,6 +564,9 @@ enum {
 
 	/* Indicate that we need to cleanup space cache v1 */
 	BTRFS_FS_CLEANUP_SPACE_CACHE_V1,
+
+	/* Indicate that we can't trust the free space tree for caching yet */
+	BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
 };
 
 /*

but 5.10.y:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=2175bf57dc9522c58d93dcd474758434a3f05c57

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e01545538e07f..30ea9780725ff 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h

@@ -146,6 +146,9 @@ enum {
 	BTRFS_FS_STATE_DEV_REPLACING,
 	/* The btrfs_fs_info created for self-tests */
 	BTRFS_FS_STATE_DUMMY_FS_INFO,
+
+	/* Indicate that we can't trust the free space tree for caching yet */
+	BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
 };
 
 #define BTRFS_BACKREF_REV_MAX		256

Both the line(Line:146 vs Line:564) and the content are wrong.

Best Regards
Wang Yugui (wangyugui@e16-tech.com)
2021/02/19