Re: [PATCH] btrfs: fix missing folio_unlock in read_merkle_tree_page error path
Qu Wenruo <[email protected]>
| Newsgroups | org.kernel.vger.stable,org.kernel.vger.linux-btrfs,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
在 2026/8/17 15:06, Hongling Zeng 写道:
> filemap_add_folio() adds the folio to the page cache and leaves it locked.
> If read_key_bytes() fails, the error path only calls folio_put() without
> first unlocking the folio, leaving it permanently locked in the page cache.
> This causes subsequent attempts to lock this folio to hang.
>
> Fix by adding folio_unlock() before folio_put() in the error handling path.
>
> Fixes: 06ed09351b67 ("btrfs: convert btrfs_read_merkle_tree_page() to use a folio")
> Cc: [email protected]
> Assisted-by: Codex:gpt-5.5
> Signed-off-by: Hongling Zeng <[email protected]>
A fix is already submitted and merged:
https://lore.kernel.org/linux-btrfs/[email protected]/
Next time let your agent to read the btrfs developer's note and check if
there is already a fix:
https://btrfs.readthedocs.io/en/latest/dev/Developer-s-FAQ.html#development-phase-linux-next-for-next
> ---
> fs/btrfs/verity.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/fs/btrfs/verity.c b/fs/btrfs/verity.c
> index 983365a73541..4431656140f8 100644
> --- a/fs/btrfs/verity.c
> +++ b/fs/btrfs/verity.c
> @@ -753,6 +753,7 @@ static struct page *btrfs_read_merkle_tree_page(struct inode *inode,
> ret = read_key_bytes(BTRFS_I(inode), BTRFS_VERITY_MERKLE_ITEM_KEY, off,
> folio_address(folio), PAGE_SIZE, folio);
> if (ret < 0) {
> + folio_unlock(folio);
> folio_put(folio);
> return ERR_PTR(ret);
> }