From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from osg.samsung.com ([64.30.133.232]:60594 "EHLO osg.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753385AbeC1OfG (ORCPT ); Wed, 28 Mar 2018 10:35:06 -0400 Date: Wed, 28 Mar 2018 11:34:56 -0300 From: Mauro Carvalho Chehab To: Dan Carpenter Cc: devel@driverdev.osuosl.org, Andy Shevchenko , Greg Kroah-Hartman , Pierre-Louis Bossart , Mauro Carvalho Chehab , Hans de Goede , Sakari Ailus , Linux Media Mailing List , Avraham Shukron , Alan Cox Subject: Re: [PATCH 12/18] media: staging: atomisp: avoid a warning if 32 bits build Message-ID: <20180328113448.51421aac@vento.lan> In-Reply-To: <20180328141329.6nhx5qcaigqwz25d@mwanda> References: <8548f74ae86b66d041e7505549453fba9fb9e63d.1522098456.git.mchehab@s-opensource.com> <313cb7db7e3fc7c7c14d2e82e249ccebcbd51ff8.1522098456.git.mchehab@s-opensource.com> <20180328141329.6nhx5qcaigqwz25d@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Wed, 28 Mar 2018 17:13:29 +0300 Dan Carpenter escreveu: > On Mon, Mar 26, 2018 at 05:10:45PM -0400, Mauro Carvalho Chehab wrote: > > Checking if a size_t value is bigger than ULONG_INT only makes > > sense if building on 64 bits, as warned by: > > drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:697 gmin_get_config_var() warn: impossible condition '(*out_len > (~0)) => (0-u32max > u32max)' > > > > Signed-off-by: Mauro Carvalho Chehab > > --- > > .../staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c b/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c > > index be0c5e11e86b..3283c1b05d6a 100644 > > --- a/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c > > +++ b/drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c > > @@ -693,9 +693,11 @@ static int gmin_get_config_var(struct device *dev, const char *var, > > for (i = 0; i < sizeof(var8) && var8[i]; i++) > > var16[i] = var8[i]; > > > > +#ifdef CONFIG_64BIT > > /* To avoid owerflows when calling the efivar API */ > > if (*out_len > ULONG_MAX) > > return -EINVAL; > > +#endif > > I should just silence this particular warning in Smatch. I feel like > this is a pretty common thing and the ifdefs aren't very pretty. :( Smatch actually warned about a real thing here: atomisp is doing a check in 32bits that it is always true. So, IMO, something is needed to prevent 32bits extra useless code somehow, perhaps via some EFI-var specific function that would do nothing on 32 bits. That's the first time I noticed this code on media (although I might have missed something), so I guess this kind of checking is actually not that common. Regards, Mauro