Commit 822fb18a82aba ("xen-netfront: wait xenbus state change when load module manually") added a new wait queue to wait on for a state change when the module is loaded manually. Unfortunately there is no wakeup anywhere to stop that waiting.

Instead of introducing a new wait queue rename the existing module_unload_q to module_wq and use it for both purposes (loading and unloading).

As any state change of the backend might be intended to stop waiting do the wake_up_all() in any case when netback_changed() is called.

Fixes: 822fb18a82aba ("xen-netfront: wait xenbus state change when load module manually") Cc: stable@vger.kernel.org #4.18 Signed-off-by: Juergen Gross jgross@suse.com --- drivers/net/xen-netfront.c | 24 ++++++++++-------------- 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 73f596a90c69..9407acbd19a9 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -87,8 +87,7 @@ struct netfront_cb { /* IRQ name is queue name with "-tx" or "-rx" appended */ #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)

-static DECLARE_WAIT_QUEUE_HEAD(module_load_q); -static DECLARE_WAIT_QUEUE_HEAD(module_unload_q); +static DECLARE_WAIT_QUEUE_HEAD(module_wq);

struct netfront_stats { u64 packets; @@ -1332,11 +1331,11 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) netif_carrier_off(netdev);

xenbus_switch_state(dev, XenbusStateInitialising); - wait_event(module_load_q, - xenbus_read_driver_state(dev->otherend) != - XenbusStateClosed && - xenbus_read_driver_state(dev->otherend) != - XenbusStateUnknown); + wait_event(module_wq, + xenbus_read_driver_state(dev->otherend) != + XenbusStateClosed && + xenbus_read_driver_state(dev->otherend) != + XenbusStateUnknown); return netdev;

exit: @@ -2010,15 +2009,14 @@ static void netback_changed(struct xenbus_device *dev,

dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state));

+ wake_up_all(&module_wq); + switch (backend_state) { case XenbusStateInitialising: case XenbusStateInitialised: case XenbusStateReconfiguring: case XenbusStateReconfigured: - break; - case XenbusStateUnknown: - wake_up_all(&module_unload_q); break;

case XenbusStateInitWait: @@ -2034,12 +2032,10 @@ static void netback_changed(struct xenbus_device *dev, break;

case XenbusStateClosed: - wake_up_all(&module_unload_q); if (dev->state == XenbusStateClosed) break; /* Missed the backend's CLOSING state -- fallthrough */ case XenbusStateClosing: - wake_up_all(&module_unload_q); xenbus_frontend_closed(dev); break; } @@ -2147,14 +2143,14 @@ static int xennet_remove(struct xenbus_device *dev)

if (xenbus_read_driver_state(dev->otherend) != XenbusStateClosed) { xenbus_switch_state(dev, XenbusStateClosing); - wait_event(module_unload_q, + wait_event(module_wq, xenbus_read_driver_state(dev->otherend) == XenbusStateClosing || xenbus_read_driver_state(dev->otherend) == XenbusStateUnknown);

xenbus_switch_state(dev, XenbusStateClosed); - wait_event(module_unload_q, + wait_event(module_wq, xenbus_read_driver_state(dev->otherend) == XenbusStateClosed || xenbus_read_driver_state(dev->otherend) ==