| Message ID | 1420626541-24277-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 225302b39afb..6a98bddd8f33 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -287,8 +287,6 @@ int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, if (!em) goto out; - if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags)) - list_move(&em->list, &tree->modified_extents); em->generation = gen; clear_bit(EXTENT_FLAG_PINNED, &em->flags); em->mod_start = em->start;
This is a note to let you know that I have just added a patch titled Btrfs: do not move em to modified list when unpinning to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt4. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 736ba53dc15f584a1d66691901bcdcdf70a2f351 Mon Sep 17 00:00:00 2001 From: Josef Bacik <jbacik@fb.com> Date: Fri, 14 Nov 2014 16:16:30 -0500 Subject: Btrfs: do not move em to modified list when unpinning commit a28046956c71985046474283fa3bcd256915fb72 upstream. We use the modified list to keep track of which extents have been modified so we know which ones are candidates for logging at fsync() time. Newly modified extents are added to the list at modification time, around the same time the ordered extent is created. We do this so that we don't have to wait for ordered extents to complete before we know what we need to log. The problem is when something like this happens log extent 0-4k on inode 1 copy csum for 0-4k from ordered extent into log sync log commit transaction log some other extent on inode 1 ordered extent for 0-4k completes and adds itself onto modified list again log changed extents see ordered extent for 0-4k has already been logged at this point we assume the csum has been copied sync log crash On replay we will see the extent 0-4k in the log, drop the original 0-4k extent which is the same one that we are replaying which also drops the csum, and then we won't find the csum in the log for that bytenr. This of course causes us to have errors about not having csums for certain ranges of our inode. So remove the modified list manipulation in unpin_extent_cache, any modified extents should have been added well before now, and we don't want them re-logged. This fixes my test that I could reliably reproduce this problem with. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- fs/btrfs/extent_map.c | 2 -- 1 file changed, 2 deletions(-) -- 2.1.4