drbd: Fix comparison of is_valid_transition()'s return code
is_valid_transition() might return SS_NOTHING_TO_DO.
The condition function _req_st_cond() returned SS_NOTHING_TO_DO, which
caused the wait_event to abort too early. Therefore drbd_req_state()
did not consume the next CL_ST_CHG_SUCCESS or SS_CW_FAILED_BY_PEER
causing serve disruption of the state machine logic...
Detaching from a single volue was one way to trigger this bug.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c
index 84512ec..69ef352 100644
--- a/drivers/block/drbd/drbd_state.c
+++ b/drivers/block/drbd/drbd_state.c
@@ -277,16 +277,16 @@
os = drbd_read_state(mdev);
ns = sanitize_state(mdev, apply_mask_val(os, mask, val), NULL);
rv = is_valid_transition(os, ns);
- if (rv == SS_SUCCESS)
+ if (rv >= SS_SUCCESS)
rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */
if (!cl_wide_st_chg(mdev, os, ns))
rv = SS_CW_NO_NEED;
if (rv == SS_UNKNOWN_ERROR) {
rv = is_valid_state(mdev, ns);
- if (rv == SS_SUCCESS) {
+ if (rv >= SS_SUCCESS) {
rv = is_valid_soft_transition(os, ns, mdev->tconn);
- if (rv == SS_SUCCESS)
+ if (rv >= SS_SUCCESS)
rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */
}
}