USB: make the autosuspend workqueue thread freezable

This patch (as881b) makes the ksuspend_usb_wq workqueue freezable.  We
don't want a rogue workqueue thread running around, unexpectedly
suspending or resuming USB devices in the middle of a system sleep
transition.

This fixes Bugzilla #8498.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 18ddc5e67e39099bc9634e9e4def4232cfc4fdef..80627b6a2bf969a3860ca28350ae051eb123c15a 100644 (file)
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -205,7 +205,11 @@ struct device_type usb_device_type = {
 
 static int ksuspend_usb_init(void)
 {
-       ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd");
+       /* This workqueue is supposed to be both freezable and
+        * singlethreaded.  Its job doesn't justify running on more
+        * than one CPU.
+        */
+       ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
        if (!ksuspend_usb_wq)
                return -ENOMEM;
        return 0;