This is a note to let you know that I've just added the patch titled
ext4: make sure group number is bumped after a inode allocation race
to the 3.4-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-make-sure-group-number-is-bumped-after-a-inode-allocation-race.patch
and it can be found in the queue-3.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a34eb503742fd25155fd6cff6163daacead9fbc3 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@xxxxxxx>
Date: Fri, 26 Jul 2013 15:15:46 -0400
Subject: ext4: make sure group number is bumped after a inode allocation race
From: Theodore Ts'o <tytso@xxxxxxx>
commit a34eb503742fd25155fd6cff6163daacead9fbc3 upstream.
When we try to allocate an inode, and there is a race between two
CPU's trying to grab the same inode, _and_ this inode is the last free
inode in the block group, make sure the group number is bumped before
we continue searching the rest of the block groups. Otherwise, we end
up searching the current block group twice, and we end up skipping
searching the last block group. So in the unlikely situation where
almost all of the inodes are allocated, it's possible that we will
return ENOSPC even though there might be free inodes in that last
block group.
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/ialloc.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -687,11 +687,8 @@ repeat_in_this_group:
ino = ext4_find_next_zero_bit((unsigned long *)
inode_bitmap_bh->b_data,
EXT4_INODES_PER_GROUP(sb), ino);
- if (ino >= EXT4_INODES_PER_GROUP(sb)) {
- if (++group == ngroups)
- group = 0;
- continue;
- }
+ if (ino >= EXT4_INODES_PER_GROUP(sb))
+ goto next_group;
if (group == 0 && (ino+1) < EXT4_FIRST_INO(sb)) {
ext4_error(sb, "reserved inode found cleared - "
"inode=%lu", ino + 1);
@@ -709,6 +706,9 @@ repeat_in_this_group:
goto got; /* we grabbed the inode! */
if (ino < EXT4_INODES_PER_GROUP(sb))
goto repeat_in_this_group;
+next_group:
+ if (++group == ngroups)
+ group = 0;
}
err = -ENOSPC;
goto out;
Patches currently in stable-queue which might be from tytso@xxxxxxx are
queue-3.4/ext4-make-sure-group-number-is-bumped-after-a-inode-allocation-race.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html