FAILED: patch "[PATCH] USB: quirks: add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for GameSir G7 SE" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] USB: quirks: add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for GameSir G7 SE" failed to apply to 6.6-stable tree

[Sasha Levin]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 40224df29729618ecd88c5c0077e71b1e82c7a3a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107053324-failed-6.6-40224df29729@kernel.org' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 40224df29729618ecd88c5c0077e71b1e82c7a3a Mon Sep 17 00:00:00 2001
From: Ali Resool Tuama <aliresool567@gmail.com>
Date: Fri, 2 Oct 2026 20:42:12 +0300
Subject: [PATCH] USB: quirks: add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for
 GameSir G7 SE

The GameSir G7 SE wired controller first enumerates as 3537:10a0 and
then re-enumerates in a mode it picks from how the host enumerated it.

When the configuration descriptor is fetched the Linux way, 9 bytes
followed by the full 80, the controller disconnects about 1 ms after
its string descriptors have been read, before SET_CONFIGURATION, and
comes back as 3537:1082, a generic HID gamepad without force feedback.

When the configuration descriptor is fetched in one 255-byte request,
as Windows does, it comes back as 3537:1010 in Xbox One (GIP) mode,
which xpad already supports, including rumble.

Skipping the device qualifier requests (USB_QUIRK_DEVICE_QUALIFIER)
makes no difference; the configuration descriptor request size alone
decides the mode. Add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for the 10a0
identity, as is already done for the ShanWan Wireless Gamepad.

Cc: stable <stable@kernel.org>
Assisted-by: claude-opus-5-5
Signed-off-by: Ali Resool Tuama <aliresool567@gmail.com>
Link: https://patch.msgid.link/20261002-master-v2-1-24b05d8792b5@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/core/quirks.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index b5b577f0b931c..a4bcbe9c913cf 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -612,6 +612,9 @@ static const struct usb_device_id usb_quirk_list[] = {
 	/* ezcap401 - BOS descriptor fetch hangs at SuperSpeed Plus */
 	{ USB_DEVICE(0x32ed, 0x0401), .driver_info = USB_QUIRK_NO_BOS },
 
+	/* GameSir G7 SE */
+	{ USB_DEVICE(0x3537, 0x10a0), .driver_info = USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE },
+
 	/* DELL USB GEN2 */
 	{ USB_DEVICE(0x413c, 0xb062), .driver_info = USB_QUIRK_NO_LPM | USB_QUIRK_RESET_RESUME },
 
-- 
2.53.0

[PATCH 6.6.y 1/2] usb: core: Add quirk for 255-bytes initial config read

[Sasha Levin]

From: Nikhil Solanke <nikhilsolanke5@gmail.com>

[ Upstream commit 152f174a13618bec1f842d2deb69245cb2ace51f ]

Certain third-party USB game controllers exposing (or spoofing) an Xbox
360-compatible interface (VID:PID 045e:028e) fail to enumerate under Linux.
The device disconnects from the bus without responding to the initial
GET_DESCRIPTOR(CONFIGURATION) request, and the kernel logs 'unable to read
config index 0 descriptor/start: -71'.

The device then falls back to a secondary Android HID mode (with a
different VID:PID), losing XInput functionality including rumble support.
The failure reproduces across multiple machines, host controller types, and
kernel versions including current mainline and LTS. The device enumerates
correctly and remains in XInput mode under Windows. Notably, the device
enumerates correctly in Android mode when the same 9-byte request
is issued for that mode's configuration descriptor, confirming the firmware
bug is specific to the XInput mode.

usbmon traces from Linux and Wireshark/USBPcap traces from Windows are
identical up to the point of failure, with no visible protocol-level
difference explaining the divergence. The root cause was identified when
Michal Pecio discovered via a QEMU bus-level capture that Windows does not
use wLength=9 for the initial config descriptor request; it uses
wLength=255. Alan Stern subsequently confirmed this with a bus
analyzer on a different USB 2.0 device, and Michal verified the behavior
goes back to Windows 95 OSR2.1.

So, add a new quirk flag USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE which causes
usb_get_configuration() to issue a 255 byte sized configuration request
instead of USB_DT_CONFIG_SIZE (9) for the initial
GET_DESCRIPTOR(CONFIGURATION) request, mimicking long-standing Windows
behavior.

This patch intentionally does not add any new VID:PID entries using this
quirk. Some affected Xbox 360-compatible controllers spoof Microsoft's
VID:PID, while genuine Microsoft controllers already enumerate correctly
and do not require this quirk. Other affected clone devices use their own
VID:PID pairs and can be added individually as they are identified.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Michal Pecio <michal.pecio@gmail.com>
Closes: https://lore.kernel.org/linux-usb/CAFgddh+JWdT4LLwMc5qjM8q_pBu-fRo2qADR5ovAKoGHWMQrRw@mail.gmail.com/
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Nikhil Solanke <nikhilsolanke5@gmail.com>
Link: https://patch.msgid.link/20260728195158.65162-2-nikhilsolanke5@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 40224df29729 ("USB: quirks: add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for GameSir G7 SE")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../admin-guide/kernel-parameters.txt         |  5 +++
 drivers/usb/core/config.c                     | 32 ++++++++++++++-----
 drivers/usb/core/quirks.c                     |  4 +++
 include/linux/usb/quirks.h                    |  3 ++
 4 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index fdbc2749fbb37..50e988c8995fc 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -6904,6 +6904,11 @@
 				q = USB_QUIRK_FORCE_ONE_CONFIG (Device
 					claims zero configurations,
 					forcing to 1);
+				r = USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE (Device
+					fails during initialization when asked for
+					9-bytes configuration descriptor request.
+					Ask for 255-bytes request instead to mirror
+					Windows' behavior);
 			Example: quirks=0781:5580:bk,0a5c:5834:gij
 
 	usbhid.mousepoll=
diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 7713526680d74..d9f874d776323 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -891,6 +891,18 @@ int usb_get_configuration(struct usb_device *dev)
 	unsigned char *bigbuffer;
 	struct usb_config_descriptor *desc;
 	int result;
+	size_t usb_config_req_size;
+
+	/*
+	 * We usually start by grabbing the first 9-bytes descriptor so we know
+	 * how long the whole configuration is. Some devices with quirky
+	 * firmware will fail enumeration, so if the quirk is set, use 255 instead,
+	 * mirroring the behavior of Windows.
+	 */
+	if (dev->quirks & USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE)
+		usb_config_req_size = 255;
+	else
+		usb_config_req_size = USB_DT_CONFIG_SIZE;
 
 	if (ncfg > USB_MAXCONFIG) {
 		dev_notice(ddev, "too many configurations: %d, "
@@ -917,15 +929,13 @@ int usb_get_configuration(struct usb_device *dev)
 	if (!dev->rawdescriptors)
 		return -ENOMEM;
 
-	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
+	desc = kmalloc(usb_config_req_size, GFP_KERNEL);
 	if (!desc)
 		return -ENOMEM;
 
 	for (cfgno = 0; cfgno < ncfg; cfgno++) {
-		/* We grab just the first descriptor so we know how long
-		 * the whole configuration is */
 		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
-		    desc, USB_DT_CONFIG_SIZE);
+		    desc, usb_config_req_size);
 		if (result < 0) {
 			dev_err(ddev, "unable to read config index %d "
 			    "descriptor/%s: %d\n", cfgno, "start", result);
@@ -935,16 +945,14 @@ int usb_get_configuration(struct usb_device *dev)
 			dev->descriptor.bNumConfigurations = cfgno;
 			break;
 		} else if (result < 4) {
-			dev_err(ddev, "config index %d descriptor too short "
-			    "(expected %i, got %i)\n", cfgno,
-			    USB_DT_CONFIG_SIZE, result);
+			dev_err(ddev, "config index %d descriptor too short (asked for %zu, got %i)\n",
+			    cfgno, usb_config_req_size, result);
 			result = -EINVAL;
 			goto err;
 		}
 		length = max((int) le16_to_cpu(desc->wTotalLength),
 		    USB_DT_CONFIG_SIZE);
 
-		/* Now that we know the length, get the whole thing */
 		bigbuffer = kmalloc(length, GFP_KERNEL);
 		if (!bigbuffer) {
 			result = -ENOMEM;
@@ -954,6 +962,13 @@ int usb_get_configuration(struct usb_device *dev)
 		if (dev->quirks & USB_QUIRK_DELAY_INIT)
 			msleep(200);
 
+		/* Skip the second read if we already got everything */
+		if (result >= length) {
+			memcpy(bigbuffer, desc, length);
+			goto store_and_parse;
+		}
+
+		/* Get the whole thing */
 		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
 		    bigbuffer, length);
 		if (result < 0) {
@@ -968,6 +983,7 @@ int usb_get_configuration(struct usb_device *dev)
 			length = result;
 		}
 
+store_and_parse:
 		dev->rawdescriptors[cfgno] = bigbuffer;
 
 		result = usb_parse_configuration(dev, cfgno,
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 6ed3805994055..23d5c30332ffb 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -143,6 +143,10 @@ static int quirks_param_set(const char *value, const struct kernel_param *kp)
 				break;
 			case 'q':
 				flags |= USB_QUIRK_FORCE_ONE_CONFIG;
+				break;
+			case 'r':
+				flags |= USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE;
+				break;
 			/* Ignore unrecognized flag characters */
 			}
 		}
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index b3cc7beab4a3c..a4043b33c2c2a 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -81,4 +81,7 @@
 /* Device claims zero configurations, forcing to 1 */
 #define USB_QUIRK_FORCE_ONE_CONFIG		BIT(18)
 
+/* Use a 255 bytes config descriptor request mirroring windows behavior */
+#define USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE	BIT(19)
+
 #endif /* __LINUX_USB_QUIRKS_H */
-- 
2.53.0

[PATCH 6.6.y 2/2] USB: quirks: add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for GameSir G7 SE

[Sasha Levin]

From: Ali Resool Tuama <aliresool567@gmail.com>

[ Upstream commit 40224df29729618ecd88c5c0077e71b1e82c7a3a ]

The GameSir G7 SE wired controller first enumerates as 3537:10a0 and
then re-enumerates in a mode it picks from how the host enumerated it.

When the configuration descriptor is fetched the Linux way, 9 bytes
followed by the full 80, the controller disconnects about 1 ms after
its string descriptors have been read, before SET_CONFIGURATION, and
comes back as 3537:1082, a generic HID gamepad without force feedback.

When the configuration descriptor is fetched in one 255-byte request,
as Windows does, it comes back as 3537:1010 in Xbox One (GIP) mode,
which xpad already supports, including rumble.

Skipping the device qualifier requests (USB_QUIRK_DEVICE_QUALIFIER)
makes no difference; the configuration descriptor request size alone
decides the mode. Add USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE for the 10a0
identity, as is already done for the ShanWan Wireless Gamepad.

Cc: stable <stable@kernel.org>
Assisted-by: claude-opus-5-5
Signed-off-by: Ali Resool Tuama <aliresool567@gmail.com>
Link: https://patch.msgid.link/20261002-master-v2-1-24b05d8792b5@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/core/quirks.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 23d5c30332ffb..ee439a2ddf316 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -607,6 +607,9 @@ static const struct usb_device_id usb_quirk_list[] = {
 	/* ezcap401 - BOS descriptor fetch hangs at SuperSpeed Plus */
 	{ USB_DEVICE(0x32ed, 0x0401), .driver_info = USB_QUIRK_NO_BOS },
 
+	/* GameSir G7 SE */
+	{ USB_DEVICE(0x3537, 0x10a0), .driver_info = USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE },
+
 	/* DELL USB GEN2 */
 	{ USB_DEVICE(0x413c, 0xb062), .driver_info = USB_QUIRK_NO_LPM | USB_QUIRK_RESET_RESUME },
 
-- 
2.53.0