summaryrefslogtreecommitdiffstats
path: root/net/sunrpc
diff options
context:
space:
mode:
authorWeston Andros Adamson <dros@netapp.com>2012-10-30 17:01:40 -0400
committerTrond Myklebust <Trond.Myklebust@netapp.com>2012-11-04 14:43:38 -0500
commit168e4b39d1afb79a7e3ea6c3bb246b4c82c6bdb9 (patch)
treef5b591952b85baf4ec3a9c7c7e29d0667724eda4 /net/sunrpc
parent3d70f8c617a436c7146ecb81df2265b4626dfe89 (diff)
downloadop-kernel-dev-168e4b39d1afb79a7e3ea6c3bb246b4c82c6bdb9.zip
op-kernel-dev-168e4b39d1afb79a7e3ea6c3bb246b4c82c6bdb9.tar.gz
SUNRPC: add WARN_ON_ONCE for potential deadlock
rpc_shutdown_client should never be called from a workqueue context. If it is, it could deadlock looping forever trying to kill tasks that are assigned to the same kworker thread (and will never run rpc_exit_task). Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/clnt.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index cdc7564b..dd2532c 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -607,6 +607,13 @@ EXPORT_SYMBOL_GPL(rpc_killall_tasks);
*/
void rpc_shutdown_client(struct rpc_clnt *clnt)
{
+ /*
+ * To avoid deadlock, never call rpc_shutdown_client from a
+ * workqueue context!
+ */
+ WARN_ON_ONCE(current->flags & PF_WQ_WORKER);
+ might_sleep();
+
dprintk_rcu("RPC: shutting down %s client for %s\n",
clnt->cl_protname,
rcu_dereference(clnt->cl_xprt)->servername);
OpenPOWER on IntegriCloud