Patch "cdc_mbim: apply "NDP to end" quirk to all Huawei devices" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

cdc_mbim: apply "NDP to end" quirk to all Huawei devices

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cdc_mbim-apply-ndp-to-end-quirk-to-all-huawei-devices.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= <[email protected]>
Date: Tue, 12 Apr 2016 16:11:12 +0200
Subject: cdc_mbim: apply "NDP to end" quirk to all Huawei devices
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From: =?UTF-8?q?Bj=C3=B8rn=20Mork?= <[email protected]>

[ Upstream commit c5b5343cfbc9f46af65033fa4f407d7b7d98371d ]

We now have a positive report of another Huawei device needing this quirk: The ME906s-158 (12d1:15c1). This is an m.2 form factor modem with no obvious relationship to the E3372 (12d1:157d) we already have a quirk entry for. This is reason enough to believe the quirk might be necessary for any number of current and future Huawei devices.

Applying the quirk to all Huawei devices, since it is crucial to any device affected by the firmware bug, while the impact on non-affected devices is negligible.

The quirk can if necessary be disabled per-device by writing N to /sys/class/net/<iface>/cdc_ncm/ndp_to_end

---
 drivers/net/usb/cdc_mbim.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

@@ -617,8 +617,13 @@ static const struct usb_device_id mbim_d
 	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 	  .driver_info = (unsigned long)&cdc_mbim_info,
 	},
-	/* Huawei E3372 fails unless NDP comes after the IP packets */
-	{ USB_DEVICE_AND_INTERFACE_INFO(0x12d1, 0x157d, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
+
+	/* Some Huawei devices, ME906s-158 (12d1:15c1) and E3372
+	 * (12d1:157d), are known to fail unless the NDP is placed
+	 * after the IP packets.  Applying the quirk to all Huawei
+	 * devices is broader than necessary, but harmless.
+	 */
+	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 	  .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
 	},
 	/* default entry */

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/cdc_mbim-apply-ndp-to-end-quirk-to-all-huawei-devices.patch