Patch "btrfs: clear ordered flag on cleaning up ordered extents" has been added to the 4.13-stable tree

This is a note to let you know that I've just added the patch titled

btrfs: clear ordered flag on cleaning up ordered extents

to the 4.13-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-clear-ordered-flag-on-cleaning-up-ordered-extents.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Naohiro Aota <[email protected]>
Date: Fri, 1 Sep 2017 17:58:47 +0900
Subject: btrfs: clear ordered flag on cleaning up ordered extents

From: Naohiro Aota <[email protected]>

commit 63d71450c8d817649a79e37d685523f988b9cc98 upstream.

Commit 524272607e88 ("btrfs: Handle delalloc error correctly to avoid ordered extent hang") introduced btrfs_cleanup_ordered_extents() to cleanup submitted ordered extents. However, it does not clear the ordered bit (Private2) of corresponding pages. Thus, the following BUG occurs from free_pages_check_bad() (on btrfs/125 with nospace_cache).

BUG: Bad page state in process btrfs  pfn:3fa787
page:ffffdf2acfe9e1c0 count:0 mapcount:0 mapping:          (null) index:0xd
flags: 0x8000000000002008(uptodate|private_2)
raw: 8000000000002008 0000000000000000 000000000000000d 00000000ffffffff
raw: ffffdf2acf5c1b20 ffffb443802238b0 0000000000000000 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set

bad because of flags: 0x2000(private_2)

This patch clears the flag same as other places calling btrfs_dec_test_ordered_pending() for every page in the specified range.

---
 fs/btrfs/inode.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

@@ -135,6 +135,18 @@ static inline void btrfs_cleanup_ordered
 						 const u64 offset,
 						 const u64 bytes)
 {
+	unsigned long index = offset >> PAGE_SHIFT;
+	unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT;
+	struct page *page;
+
+	while (index <= end_index) {
+		page = find_get_page(inode->i_mapping, index);
+		index++;
+		if (!page)
+			continue;
+		ClearPagePrivate2(page);
+		put_page(page);
+	}
 	return __endio_write_update_ordered(inode, offset + PAGE_SIZE,
 					    bytes - PAGE_SIZE, false);
 }

Patches currently in stable-queue which might be from [email protected] are

queue-4.13/btrfs-propagate-error-to-btrfs_cmp_data_prepare-caller.patch queue-4.13/btrfs-fix-null-pointer-dereference-from-free_reloc_roots.patch queue-4.13/btrfs-clear-ordered-flag-on-cleaning-up-ordered-extents.patch queue-4.13/btrfs-finish-ordered-extent-cleaning-if-no-progress-is-found.patch