SUNRPC: Lock the transport layer on shutdown
Avoid all races with the connect/disconnect handlers by taking the
transport lock.
Reported-by:"Suzuki K. Poulose" <suzuki.poulose@arm.com>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index ab5dd62..2e98f4a 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -614,6 +614,7 @@
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
xprt->ops->close(xprt);
xprt_release_write(xprt, NULL);
+ wake_up_bit(&xprt->state, XPRT_LOCKED);
}
/**
@@ -723,6 +724,7 @@
xprt->ops->release_xprt(xprt, NULL);
out:
spin_unlock_bh(&xprt->transport_lock);
+ wake_up_bit(&xprt->state, XPRT_LOCKED);
}
/**
@@ -1394,6 +1396,10 @@
static void xprt_destroy(struct rpc_xprt *xprt)
{
dprintk("RPC: destroying transport %p\n", xprt);
+
+ /* Exclude transport connect/disconnect handlers */
+ wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE);
+
del_timer_sync(&xprt->timer);
rpc_xprt_debugfs_unregister(xprt);