2014-07-25 05:13:31

by Reyad Attiyat

Subject: [PATCH] hid: usbhid: Use flag HID_DISCONNECTED when a usb device is removed

Set disconnected flag in struct usbhid when a usb device
is removed. Check for disconnected flag before sending urb
requests. This prevents a kernel panic when a hid driver calls
hid_hw_request() after removing a usb device.

Signed-off-by: Reyad Attiyat <[email protected]>
---
drivers/hid/usbhid/hid-core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 7b88f4c..c8fa957 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -536,7 +536,8 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re
int head;
struct usbhid_device *usbhid = hid->driver_data;

- if ((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN)
+ if (((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN) ||
+ test_bit(HID_DISCONNECTED, &usbhid->iofl))
return;

if (usbhid->urbout && dir == USB_DIR_OUT && report->type == HID_OUTPUT_REPORT) {
@@ -1366,6 +1367,9 @@ static void usbhid_disconnect(struct usb_interface *intf)
return;

usbhid = hid->driver_data;
+ spin_lock_irq(&usbhid->lock); /* Sync with error and led handlers */
+ set_bit(HID_DISCONNECTED, &usbhid->iofl);
+ spin_unlock_irq(&usbhid->lock);
hid_destroy_device(hid);
kfree(usbhid);
}
--
1.9.3

2014-07-25 19:06:56

by Reyad Attiyat

Subject: Re: [PATCH] hid: usbhid: Use flag HID_DISCONNECTED when a usb device is removed

The kernel panic happened when the iio sensor hid usb device was
removed. It tries to set the power state by calling hid_hw_request().
This was on kernel 3.16-rc6
https://gist.github.com/soda0289/2ff543d9cfff6f92c360#file-kernel-panic-when-iio-sensor-usb-device-is-removed

On Fri, Jul 25, 2014 at 12:13 AM, Reyad Attiyat <[email protected]> wrote:
> Set disconnected flag in struct usbhid when a usb device
> is removed. Check for disconnected flag before sending urb
> requests. This prevents a kernel panic when a hid driver calls
> hid_hw_request() after removing a usb device.
>
> Signed-off-by: Reyad Attiyat <[email protected]>
> ---
> drivers/hid/usbhid/hid-core.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
> index 7b88f4c..c8fa957 100644
> --- a/drivers/hid/usbhid/hid-core.c
> +++ b/drivers/hid/usbhid/hid-core.c
> @@ -536,7 +536,8 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re
> int head;
> struct usbhid_device *usbhid = hid->driver_data;
>
> - if ((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN)
> + if (((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN) ||
> + test_bit(HID_DISCONNECTED, &usbhid->iofl))
> return;
>
> if (usbhid->urbout && dir == USB_DIR_OUT && report->type == HID_OUTPUT_REPORT) {
> @@ -1366,6 +1367,9 @@ static void usbhid_disconnect(struct usb_interface *intf)
> return;
>
> usbhid = hid->driver_data;
> + spin_lock_irq(&usbhid->lock); /* Sync with error and led handlers */
> + set_bit(HID_DISCONNECTED, &usbhid->iofl);
> + spin_unlock_irq(&usbhid->lock);
> hid_destroy_device(hid);
> kfree(usbhid);
> }
> --
> 1.9.3
>

2014-07-29 11:06:55

by Jiri Kosina

Subject: Re: [PATCH] hid: usbhid: Use flag HID_DISCONNECTED when a usb device is removed

On Fri, 25 Jul 2014, Reyad Attiyat wrote:

> Set disconnected flag in struct usbhid when a usb device
> is removed. Check for disconnected flag before sending urb
> requests. This prevents a kernel panic when a hid driver calls
> hid_hw_request() after removing a usb device.
>
> Signed-off-by: Reyad Attiyat <[email protected]>

I've included the full oops output into the changelog and applied, thanks.

--
Jiri Kosina
SUSE Labs