[PATCH v3] USB: gadget: core: adjust uevent timing on gadget unbind

From: Roy Luo
Date: Tue Nov 28 2023 - 17:18:03 EST


The KOBJ_CHANGE uevent is sent before gadget unbind is actually
executed, resulting in inaccurate uevent emitted at incorrect timing
(the uevent would have USB_UDC_DRIVER variable set while it would
soon be removed).
Move the KOBJ_CHANGE uevent to the end of the unbind function so that
uevent is sent only after the change has been made.

Fixes: 2ccea03a8f7e ("usb: gadget: introduce UDC Class")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Roy Luo <royluo@xxxxxxxxxx>
---
Changes since v1: add Fixes tag
Changes since v2: add cc stable@xxxxxxxxxxxxxxx
---
drivers/usb/gadget/udc/core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index ded9531f141b..d59f94464b87 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1646,8 +1646,6 @@ static void gadget_unbind_driver(struct device *dev)

dev_dbg(&udc->dev, "unbinding gadget driver [%s]\n", driver->function);

- kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
-
udc->allow_connect = false;
cancel_work_sync(&udc->vbus_work);
mutex_lock(&udc->connect_lock);
@@ -1667,6 +1665,8 @@ static void gadget_unbind_driver(struct device *dev)
driver->is_bound = false;
udc->driver = NULL;
mutex_unlock(&udc_lock);
+
+ kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
}

/* ------------------------------------------------------------------------- */

base-commit: 9b6de136b5f0158c60844f85286a593cb70fb364
--
2.43.0.rc1.413.gea7ed67945-goog