diff options
author | Philipp Reisner <philipp.reisner@linbit.com> | 2012-01-16 06:14:01 -0500 |
---|---|---|
committer | Philipp Reisner <philipp.reisner@linbit.com> | 2012-05-09 09:16:34 -0400 |
commit | fc28845bc005995b41ae8c83c7922d088f0ad228 (patch) | |
tree | cb5f28c4c0cfb06f46b9e1b0d7e7efcdfc132f90 /drivers/block/drbd/drbd_req.c | |
parent | 031a7c173ffda664ac5551bd13c313e513dd87a7 (diff) |
drbd: Fix a potential race that could case data inconsistency
When we have a write request and a state change C_WF_BITMAP_S -> C_SYNC_SOURCE
at the same time, and it happens that the line
remote = remote && drbd_should_do_remote(s);
stills sees C_WF_BITMAP_S, and
send_oos = rw == WRITE && drbd_should_send_oos(s);
already sees C_SYNC_SOURCE both are 0.
This causes the write to not be mirrored, but marked as out-of-sync on the
Sync_Source node.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_req.c')
-rw-r--r-- | drivers/block/drbd/drbd_req.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 810070146862..4fc7f98d9856 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c | |||
@@ -786,6 +786,7 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, uns | |||
786 | int local, remote, send_oos = 0; | 786 | int local, remote, send_oos = 0; |
787 | int err = -EIO; | 787 | int err = -EIO; |
788 | int ret = 0; | 788 | int ret = 0; |
789 | union drbd_state s; | ||
789 | 790 | ||
790 | /* allocate outside of all locks; */ | 791 | /* allocate outside of all locks; */ |
791 | req = drbd_req_new(mdev, bio); | 792 | req = drbd_req_new(mdev, bio); |
@@ -847,8 +848,9 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, uns | |||
847 | drbd_al_begin_io(mdev, sector); | 848 | drbd_al_begin_io(mdev, sector); |
848 | } | 849 | } |
849 | 850 | ||
850 | remote = remote && drbd_should_do_remote(mdev->state); | 851 | s = mdev->state; |
851 | send_oos = rw == WRITE && drbd_should_send_oos(mdev->state); | 852 | remote = remote && drbd_should_do_remote(s); |
853 | send_oos = rw == WRITE && drbd_should_send_oos(s); | ||
852 | D_ASSERT(!(remote && send_oos)); | 854 | D_ASSERT(!(remote && send_oos)); |
853 | 855 | ||
854 | if (!(local || remote) && !is_susp(mdev->state)) { | 856 | if (!(local || remote) && !is_susp(mdev->state)) { |