Re: [PATCH] usb: core: Add error handling in usb_reset_device for autoresume failure

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Feb 20, 2025 at 05:52:18PM +0800, Wentao Liang wrote:
> In usb_reset_device(),  the function continues execution and
> calls usb_autosuspend_device() after usb_autosuspend_device fails.
> 
> To fix this, add error handling for usb_autoresume_device()
> and return the error code immediately. This ensures that
> usb_autosuspend_device() is not called when usb_autoresume_device()
> fails, maintaining device state consistency.
> 
> Fixes: 94fcda1f8ab5 ("usbcore: remove unused argument in autosuspend")
> Cc: stable@vger.kernel.org # 2.6.20+
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
>  drivers/usb/core/hub.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 21ac9b464696..f2efdbdd1533 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -6292,7 +6292,9 @@ int usb_reset_device(struct usb_device *udev)
>  	noio_flag = memalloc_noio_save();
>  
>  	/* Prevent autosuspend during the reset */
> -	usb_autoresume_device(udev);

Have you ever seen this function fail?

> +	ret = usb_autoresume_device(udev);
> +	if (ret < 0)

if (ret) please.

Also, how was this tested?  How was it found?

thanks,

greg k-h