Re: [PATCH] hwmon: (cros-ec_hwmon) Fix access to restricted __le16

[Guenter Roeck]

On 6/6/24 13:48, Thomas Weißschuh wrote:
> On 2024-06-06 13:16:59+0000, Guenter Roeck wrote:
> > On 6/6/24 12:53, Thomas Weißschuh wrote:
> > > Thanks!
> > >
> > > On 2024-06-06 11:05:07+0000, Guenter Roeck wrote:
> > > > 0-day complains:
> > > >
> > > > drivers-hwmon-cros_ec_hwmon.c:sparse:sparse:cast-to-restricted-__le16
> > > >
> > > > Fix by using a __le16 typed variable as parameter to le16_to_cpu().
> > > >
> > > > Fixes: bc3e45258096 ("hwmon: add ChromeOS EC driver")
> > > > Cc: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> > > > Cc: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
> > > > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> > >
> > > Acked-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> > >
> > > Guenter, does sparse work locally for you?
> >
> > It does, but I use the version from git://repo.or.cz/smatch.git.
>
> That does indeed look much better, thanks.
>
>
> I have another question about the endianness conversion in general.
> The only places I see doing a conversion are
> cros_ec_sensors_cmd_read_u16() and the original cros_ec hwmon driver.
>
> Also the documentation of the EC protocol does not specify anything in
> that regard.
> Instead there is the following comment in host_event_set_bit():
>
>     /*
>      * The overall host event implementation assumes it's running on and
>      * communicating with little-endian architectures.
>      */
>
> Can the conversion be dropped?


Unless it is wrong I don't see a reason to drop it.

Guenter