diff options
author | Stefan Behrens <sbehrens@giantdisaster.de> | 2012-11-27 20:10:21 +0400 |
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committer | Chris Mason <chris.mason@fusionio.com> | 2012-12-17 05:46:13 +0400 |
commit | cb3806ec88a7e1e9d1fbde34cbc0bf153b7e7c3f (patch) | |
tree | 2e02ffad4235261cdb04b1eca1cbc9e7e83a3798 | |
parent | b66f00da0cfceb856c17706b77906b63437f6fda (diff) | |
download | linux-cb3806ec88a7e1e9d1fbde34cbc0bf153b7e7c3f.tar.xz |
Btrfs: fix race in check-integrity caused by usage of bitfield
The structure member mirror_num is modified concurrently to the
structure member is_iodone. This doesn't require any locking by
design, unless everything is stored in the same 32 bits of a
bit field. This was the case and xfstest 284 was able to
trigger false warnings from the checker code. This patch
seperates the bits and fixes the race.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
-rw-r--r-- | fs/btrfs/check-integrity.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c index badc6f141b6f..11d47bfb62b4 100644 --- a/fs/btrfs/check-integrity.c +++ b/fs/btrfs/check-integrity.c @@ -137,7 +137,7 @@ struct btrfsic_block { unsigned int never_written:1; /* block was added because it was * referenced, not because it was * written */ - unsigned int mirror_num:2; /* large enough to hold + unsigned int mirror_num; /* large enough to hold * BTRFS_SUPER_MIRROR_MAX */ struct btrfsic_dev_state *dev_state; u64 dev_bytenr; /* key, physical byte num on disk */ |