[PATCH] race on rpc code

[Eduardo Pereira Habkost]

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Hi!

The following patch fixes a race on the rpc code, it is the
same race that was reported some weeks ago:
http://marc.theaimsgroup.com/?l=3Dlinux-kernel&m=3D104462124226133&w=3D2

After some minutes doing transfer of multiple files in parallel, it Oopses
at xprt_timer because task->tk_client is NULL. It can happens because
rpc_del_timer don't call timer_del_sync if the timer is running. But
if xprt_timer is running, it can can setup itself to run again, even if
the task is already being released by rpc_release_task.

--=20
Eduardo

diff -Nru a/net/sunrpc/sched.c b/net/sunrpc/sched.c
--- a/net/sunrpc/sched.c        Mon Mar 17 20:19:20 2003
+++ b/net/sunrpc/sched.c        Mon Mar 17 20:19:20 2003
@@ -169,10 +169,8 @@
 static inline void
 rpc_delete_timer(struct rpc_task *task)
 {
-       if (timer_pending(&task->tk_timer)) {
-               dprintk("RPC: %4d deleting timer\n", task->tk_pid);
-               del_timer_sync(&task->tk_timer);
-       }
+       dprintk("RPC: %4d deleting timer\n", task->tk_pid);
+       del_timer_sync(&task->tk_timer);
 }

 /*

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