RDMA/iwcm: Don't touch cmid after dropping reference
The function cm_work_handler() cannot touch the cm_id after it derefs
it, because it might be freed on another concurrent thread. If there
are more work items queued for this cm_id, then we know there must be
more references because they are added when the work items are queued.
So in the while loop inside cm_work_handler(), after derefing, if the
queue is empty, then exit the function. Otherwise we know it's safe
to re-acquire the lock.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/core/iwcm.c b/drivers/infiniband/core/iwcm.c
index 0bb99bb..c47c203 100644
--- a/drivers/infiniband/core/iwcm.c
+++ b/drivers/infiniband/core/iwcm.c
@@ -878,6 +878,8 @@
}
return;
}
+ if (empty)
+ return;
spin_lock_irqsave(&cm_id_priv->lock, flags);
}
spin_unlock_irqrestore(&cm_id_priv->lock, flags);