This is a note to let you know that I've just added the patch titled
ext4: trim allocation requests to group size
to the 4.9-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:
ext4-trim-allocation-requests-to-group-size.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cd648b8a8fd5071d232242d5ee7ee3c0815776af Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@xxxxxxx>
Date: Fri, 27 Jan 2017 14:34:30 -0500
Subject: ext4: trim allocation requests to group size
From: Jan Kara <jack@xxxxxxx>
commit cd648b8a8fd5071d232242d5ee7ee3c0815776af upstream.
If filesystem groups are artifically small (using parameter -g to
mkfs.ext4), ext4_mb_normalize_request() can result in a request that is
larger than a block group. Trim the request size to not confuse
allocation code.
Reported-by: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/mballoc.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3123,6 +3123,13 @@ ext4_mb_normalize_request(struct ext4_al
if (ar->pright && start + size - 1 >= ar->lright)
size -= start + size - ar->lright;
+ /*
+ * Trim allocation request for filesystems with artificially small
+ * groups.
+ */
+ if (size > EXT4_BLOCKS_PER_GROUP(ac->ac_sb))
+ size = EXT4_BLOCKS_PER_GROUP(ac->ac_sb);
+
end = start + size;
/* check we don't cross already preallocated blocks */
Patches currently in stable-queue which might be from jack@xxxxxxx are
queue-4.9/ext4-fix-data-corruption-in-data-journal-mode.patch
queue-4.9/ext4-trim-allocation-requests-to-group-size.patch