[PATCH] IB: fix userspace CM deadlock
Fix deadlock condition resulting from trying to destroy a cm_id
from the context of a CM thread. The synchronization around the
ucm context structure is simplified as a result, and some simple
code cleanup is included.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/core/ucm.h b/drivers/infiniband/core/ucm.h
index 6d36606..039e8a3 100644
--- a/drivers/infiniband/core/ucm.h
+++ b/drivers/infiniband/core/ucm.h
@@ -48,9 +48,7 @@
struct ib_ucm_file {
struct semaphore mutex;
struct file *filp;
- /*
- * list of pending events
- */
+
struct list_head ctxs; /* list of active connections */
struct list_head events; /* list of pending events */
wait_queue_head_t poll_wait;
@@ -58,12 +56,11 @@
struct ib_ucm_context {
int id;
- int ref;
- int error;
+ wait_queue_head_t wait;
+ atomic_t ref;
struct ib_ucm_file *file;
struct ib_cm_id *cm_id;
- struct semaphore mutex;
struct list_head events; /* list of pending events. */
struct list_head file_list; /* member in file ctx list */