There's a race condition that leads to a NULL pointer dereference if you disable quotas while a quota rescan is running. To fix this, we just need to wait for the quota rescan worker to actually exit before tearing down the quota structures.
Signed-off-by: Justin Maggard <[email protected]> --- fs/btrfs/qgroup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 75c0249..a7cf504 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -993,9 +993,10 @@ int btrfs_quota_disable(struct btrfs_trans_handle *trans, mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) goto out; - spin_lock(&fs_info->qgroup_lock); fs_info->quota_enabled = 0; fs_info->pending_quota_state = 0; + btrfs_qgroup_wait_for_completion(fs_info); + spin_lock(&fs_info->qgroup_lock); quota_root = fs_info->quota_root; fs_info->quota_root = NULL; fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON; -- 2.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
