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Date: Thu, 15 Aug 2024 09:07:41 -0700
From: Kees Cook <kees@kernel.org>
To: Jani Nikula <jani.nikula@intel.com>
Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	intel-gfx@lists.freedesktop.org, Andy Shevchenko <andy@kernel.org>
Subject: Re: [PATCH v2 2/2] drm: use mem_is_zero() instead of !memchr_inv(s,
 0, n)
Message-ID: <202408150907.5B5C5FCDF@keescook>
References: <20240814100035.3100852-1-jani.nikula@intel.com>
 <20240814100035.3100852-2-jani.nikula@intel.com>
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In-Reply-To: <20240814100035.3100852-2-jani.nikula@intel.com>

On Wed, Aug 14, 2024 at 01:00:35PM +0300, Jani Nikula wrote:
> Use the mem_is_zero() helper where possible.
> 
> Conversion done using cocci:
> 
> | @@
> | expression PTR;
> | expression SIZE;
> | @@
> |
> |   <...
> | (
> | - memchr_inv(PTR, 0, SIZE) == NULL
> | + mem_is_zero(PTR, SIZE)
> | |
> | - !memchr_inv(PTR, 0, SIZE)
> | + mem_is_zero(PTR, SIZE)
> | |
> | - memchr_inv(PTR, 0, SIZE)
> | + !mem_is_zero(PTR, SIZE)
> | )
> |   ...>
> 
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Thanks for these patches! Since drm is the first user, feel free to
carry it there unless you'd prefer I carry it in my trees?

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook