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

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

[Frieder Schrempf]

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

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

[RaghuramChary.Jallipalli]

> 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>

Reviewed-by: Raghuram Chary J <RaghuramChary.Jallipalli@microchip.com>

-Raghu

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

[David Miller]

From: Frieder Schrempf <frieder.schrempf@kontron.de>
Date: Wed, 31 Oct 2018 22:52:19 +0100

> 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>

Applied and queued up for -stable.