This is a note to let you know that I've just added the patch titled btrfs: subpage: make btrfs_submit_compressed_write() compatible to the 5.14-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-subpage-make-btrfs_submit_compressed_write-com.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 4fa2ff4709d87e12e150d129663270a7beaa1ffe Author: Qu Wenruo <wqu@xxxxxxxx> Date: Mon Sep 27 15:22:00 2021 +0800 btrfs: subpage: make btrfs_submit_compressed_write() compatible [ Upstream commit bbbff01a47bfe1b7733c5ccac6a78ff6d7a8954f ] There is a WARN_ON() checking if @start is aligned to PAGE_SIZE, not sectorsize, which will cause false alert for subpage. Fix it to check against sectorsize. Furthermore: - Use ASSERT() to do the check So that in the future we may skip the check for production build - Also check alignment for @len Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 30d82cdf128cf..86f7eb75ea506 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -404,7 +404,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, const bool use_append = btrfs_use_zone_append(inode, disk_start); const unsigned int bio_op = use_append ? REQ_OP_ZONE_APPEND : REQ_OP_WRITE; - WARN_ON(!PAGE_ALIGNED(start)); + ASSERT(IS_ALIGNED(start, fs_info->sectorsize) && + IS_ALIGNED(len, fs_info->sectorsize)); cb = kmalloc(compressed_bio_size(fs_info, compressed_len), GFP_NOFS); if (!cb) return BLK_STS_RESOURCE;