Re: [PATCH 1/3] usb: gadget: udc: Avoid tasklet passing a global - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Kees Cook <keescook@chromium.org>
Cc: Kuppuswamy Sathyanarayanan
	<sathyanarayanan.kuppuswamy@linux.intel.com>,
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	"David S. Miller" <davem@davemloft.net>
Subject: Re: [PATCH 1/3] usb: gadget: udc: Avoid tasklet passing a global
Date: Thu, 16 Jul 2020 09:28:23 +0200	[thread overview]
Message-ID: <20200716072823.GA971895@kroah.com> (raw)
In-Reply-To: <20200716030847.1564131-2-keescook@chromium.org>

On Wed, Jul 15, 2020 at 08:08:45PM -0700, Kees Cook wrote:
> There's no reason for the tasklet callback to set an argument since it
> always uses a global. Instead, use the global directly, in preparation
> for converting the tasklet subsystem to modern callback conventions.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
>  drivers/usb/gadget/udc/snps_udc_core.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
> index 3fcded31405a..afdd28f332ce 100644
> --- a/drivers/usb/gadget/udc/snps_udc_core.c
> +++ b/drivers/usb/gadget/udc/snps_udc_core.c
> @@ -96,9 +96,7 @@ static int stop_pollstall_timer;
>  static DECLARE_COMPLETION(on_pollstall_exit);
>  
>  /* tasklet for usb disconnect */
> -static DECLARE_TASKLET(disconnect_tasklet, udc_tasklet_disconnect,
> -		(unsigned long) &udc);
> -
> +static DECLARE_TASKLET(disconnect_tasklet, udc_tasklet_disconnect, 0);
>  
>  /* endpoint names used for print */
>  static const char ep0_string[] = "ep0in";
> @@ -1661,7 +1659,7 @@ static void usb_disconnect(struct udc *dev)
>  /* Tasklet for disconnect to be outside of interrupt context */
>  static void udc_tasklet_disconnect(unsigned long par)
>  {
> -	struct udc *dev = (struct udc *)(*((struct udc **) par));
> +	struct udc *dev = udc;
>  	u32 tmp;
>  
>  	DBG(dev, "Tasklet disconnect\n");

Feel free to just take this in your tree, no need to wait for the USB
stuff to land.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>