Re: [PATCH] usb: gadget: u_ether: Set is_suspend flag if remote wakeup fails

[Greg Kroah-Hartman]

On Wed, Feb 12, 2025 at 03:38:40PM +0530, Prashanth K wrote:
> Currently while UDC suspends, u_ether attempts to remote wakeup
> the host if there are any pending transfers. However, if remote
> wakeup fails, the UDC remains suspended but the is_suspend flag
> is not set. And since is_suspend flag isn't set, the subsequent
> eth_start_xmit() would queue USB requests to suspended UDC.
> 
> To fix this, bail out from gether_suspend() only if remote wakeup
> operation is successful.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 0a1af6dfa077 ("usb: gadget: f_ecm: Add suspend/resume and remote wakeup support")
> Signed-off-by: Prashanth K <prashanth.k@xxxxxxxxxxxxxxxx>
> ---
>  drivers/usb/gadget/function/u_ether.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c
> index 09e2838917e2..f58590bf5e02 100644
> --- a/drivers/usb/gadget/function/u_ether.c
> +++ b/drivers/usb/gadget/function/u_ether.c
> @@ -1052,8 +1052,8 @@ void gether_suspend(struct gether *link)
>  		 * There is a transfer in progress. So we trigger a remote
>  		 * wakeup to inform the host.
>  		 */
> -		ether_wakeup_host(dev->port_usb);
> -		return;
> +		if (!ether_wakeup_host(dev->port_usb))
> +			return;

What about the other place in the driver where this function is called
but the return value is ignored?

thanks,

greg k-h