diff options
author | Tilman Schmidt <tilman@imap.cc> | 2012-10-24 08:44:32 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-12-03 11:47:11 -0800 |
commit | 6495a1b5bc6f9e55eff414975609fef9e4a73662 (patch) | |
tree | e356c3755bdcf1e0e858637c10de888a4d52751f | |
parent | 06096cf239242e915ee13c48c10306828c828527 (diff) |
bas_gigaset: fix pre_reset handling
commit c6fdd8e5d0c65bb8821dc6da26ee1a2ddd58b3cc upstream.
The delayed work function int_in_work() may call usb_reset_device()
and thus, indirectly, the driver's pre_reset method. Trying to
cancel the work synchronously in that situation would deadlock.
Fix by avoiding cancel_work_sync() in the pre_reset method.
If the reset was NOT initiated by int_in_work() this might cause
int_in_work() to run after the post_reset method, with urb_int_in
already resubmitted, so handle that case gracefully.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/isdn/gigaset/bas-gigaset.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/isdn/gigaset/bas-gigaset.c b/drivers/isdn/gigaset/bas-gigaset.c index afa080258bf..5e1bf61e80e 100644 --- a/drivers/isdn/gigaset/bas-gigaset.c +++ b/drivers/isdn/gigaset/bas-gigaset.c @@ -616,7 +616,13 @@ static void int_in_work(struct work_struct *work) if (rc == 0) /* success, resubmit interrupt read URB */ rc = usb_submit_urb(urb, GFP_ATOMIC); - if (rc != 0 && rc != -ENODEV) { + + switch (rc) { + case 0: /* success */ + case -ENODEV: /* device gone */ + case -EINVAL: /* URB already resubmitted, or terminal badness */ + break; + default: /* failure: try to recover by resetting the device */ dev_err(cs->dev, "clear halt failed: %s\n", get_usb_rcmsg(rc)); rc = usb_lock_device_for_reset(ucs->udev, ucs->interface); if (rc == 0) { @@ -2437,7 +2443,9 @@ static void gigaset_disconnect(struct usb_interface *interface) } /* gigaset_suspend - * This function is called before the USB connection is suspended. + * This function is called before the USB connection is suspended + * or before the USB device is reset. + * In the latter case, message == PMSG_ON. */ static int gigaset_suspend(struct usb_interface *intf, pm_message_t message) { @@ -2493,7 +2501,12 @@ static int gigaset_suspend(struct usb_interface *intf, pm_message_t message) del_timer_sync(&ucs->timer_atrdy); del_timer_sync(&ucs->timer_cmd_in); del_timer_sync(&ucs->timer_int_in); - cancel_work_sync(&ucs->int_in_wq); + + /* don't try to cancel int_in_wq from within reset as it + * might be the one requesting the reset + */ + if (message.event != PM_EVENT_ON) + cancel_work_sync(&ucs->int_in_wq); gig_dbg(DEBUG_SUSPEND, "suspend complete"); return 0; |