diff options
| author | Dave Chinner <dchinner@redhat.com> | 2018-05-09 16:47:34 +0200 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2018-05-10 17:56:41 +0200 |
| commit | 22525c17ed133202088f6f05acd9c53790a7121d (patch) | |
| tree | 1447ecb5ace55b30f6ed03cf47f7121cce42418f /fs/xfs/xfs_dquot.c | |
| parent | xfs: add missing rmap error return (diff) | |
| download | linux-22525c17ed133202088f6f05acd9c53790a7121d.tar.xz linux-22525c17ed133202088f6f05acd9c53790a7121d.zip | |
xfs: log item flags are racy
The log item flags contain a field that is protected by the AIL
lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to
set and clear these flags, but most of the updates and checks are
not done with the AIL lock held and so are susceptible to update
races.
Fix this by changing the log item flags to use atomic bitops rather
than be reliant on the AIL lock for update serialisation.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Diffstat (limited to 'fs/xfs/xfs_dquot.c')
| -rw-r--r-- | fs/xfs/xfs_dquot.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c index d0880c1add41..4ca9c39879ae 100644 --- a/fs/xfs/xfs_dquot.c +++ b/fs/xfs/xfs_dquot.c @@ -913,9 +913,9 @@ xfs_qm_dqflush_done( * since it's cheaper, and then we recheck while * holding the lock before removing the dquot from the AIL. */ - if ((lip->li_flags & XFS_LI_IN_AIL) && + if (test_bit(XFS_LI_IN_AIL, &lip->li_flags) && ((lip->li_lsn == qip->qli_flush_lsn) || - (lip->li_flags & XFS_LI_FAILED))) { + test_bit(XFS_LI_FAILED, &lip->li_flags))) { /* xfs_trans_ail_delete() drops the AIL lock. */ spin_lock(&ailp->ail_lock); @@ -926,8 +926,7 @@ xfs_qm_dqflush_done( * Clear the failed state since we are about to drop the * flush lock */ - if (lip->li_flags & XFS_LI_FAILED) - xfs_clear_li_failed(lip); + xfs_clear_li_failed(lip); spin_unlock(&ailp->ail_lock); } } |