[PATCH v2] usbnet: smsc95xx: disable carrier check while suspending

From: Frieder Schrempf <frieder.schrempf@kontron.de>
To: steve.glendinning@shawell.net, UNGLinuxDriver@microchip.com
Cc: davem@davemloft.net, netdev@vger.kernel.org,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	Frieder Schrempf <frieder.schrempf@kontron.de>,
	stable@vger.kernel.org
Subject: [PATCH v2] usbnet: smsc95xx: disable carrier check while suspending
Date: Wed, 31 Oct 2018 22:52:19 +0100	[thread overview]
Message-ID: <1541022739-24678-1-git-send-email-frieder.schrempf@kontron.de> (raw)

We need to make sure, that the carrier check polling is disabled
while suspending. Otherwise we can end up with usbnet_read_cmd()
being issued when only usbnet_read_cmd_nopm() is allowed. If this
happens, read operations lock up.

Fixes: d69d169493 ("usbnet: smsc95xx: fix link detection for disabled autonegotiation")
Cc: <stable@vger.kernel.org>
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
Changes in v2:
 * move cancel_delayed_work_sync() to correct error path

 drivers/net/usb/smsc95xx.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 262e7a3..2d17f3b 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -1598,6 +1598,8 @@ static int smsc95xx_suspend(struct usb_interface *intf, pm_message_t message)
 		return ret;
 	}
 
+	cancel_delayed_work_sync(&pdata->carrier_check);
+
 	if (pdata->suspend_flags) {
 		netdev_warn(dev->net, "error during last resume\n");
 		pdata->suspend_flags = 0;
@@ -1840,6 +1842,11 @@ static int smsc95xx_suspend(struct usb_interface *intf, pm_message_t message)
 	 */
 	if (ret && PMSG_IS_AUTO(message))
 		usbnet_resume(intf);
+
+	if (ret)
+		schedule_delayed_work(&pdata->carrier_check,
+				      CARRIER_CHECK_DELAY);
+
 	return ret;
 }
 
-- 
2.7.4

