staging: usbip: fix shutdown problems.

When shuting down the tcp_rx and tcp_tx threads first check if they are
not closed already (maybe because an error caused them to return).

Signed-off-by: Arjan Mels <arjan.mels@gmx.net>
Cc: Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>
Cc: Max Vozeler <max@vozeler.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/staging/usbip/stub_dev.c b/drivers/staging/usbip/stub_dev.c
index 8214c353d9f..bce7d039346 100644
--- a/drivers/staging/usbip/stub_dev.c
+++ b/drivers/staging/usbip/stub_dev.c
@@ -220,8 +220,10 @@ static void stub_shutdown_connection(struct usbip_device *ud)
         }
 
         /* 1. stop threads */
-        kthread_stop(ud->tcp_rx);
-        kthread_stop(ud->tcp_tx);
+        if (ud->tcp_rx && !task_is_dead(ud->tcp_rx))
+                kthread_stop(ud->tcp_rx);
+        if (ud->tcp_tx && !task_is_dead(ud->tcp_tx))
+                kthread_stop(ud->tcp_tx);
 
         /* 2. close the socket */
         /*