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References: <20240527094320.2653177-1-jani.nikula@intel.com> <20240527094320.2653177-2-jani.nikula@intel.com>
In-Reply-To: <20240527094320.2653177-2-jani.nikula@intel.com>
From: Andy Shevchenko <andy.shevchenko@gmail.com>
Date: Mon, 27 May 2024 16:19:35 +0300
Message-ID: <CAHp75Ve0vyOv3KNY_7286wLKd8u6HOvu0Trm17rs46h-BOGsfA@mail.gmail.com>
Subject: Re: [PATCH 2/2] drm: use mem_is_zero() instead of !memchr_inv(s, 0, n)
To: Jani Nikula <jani.nikula@intel.com>
Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, 
	intel-gfx@lists.freedesktop.org, Kees Cook <keescook@chromium.org>, 
	Andy Shevchenko <andy@kernel.org>
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On Mon, May 27, 2024 at 12:43=E2=80=AFPM Jani Nikula <jani.nikula@intel.com=
> wrote:
>
> Use the mem_is_zero() helper where possible.

..

> -       if (memchr_inv(guid, 0, 16) =3D=3D NULL) {
> +       if (mem_is_zero(guid, 16)) {
>                 tmp64 =3D get_jiffies_64();
>                 memcpy(&guid[0], &tmp64, sizeof(u64));
>                 memcpy(&guid[8], &tmp64, sizeof(u64));

What is the type of guid? Shouldn't it be guid_t with the respective
guid_is_null()

..

> -       if (memchr_inv(guid, 0, 16))
> +       if (!mem_is_zero(guid, 16))
>                 return true;

Ditto.

--=20
With Best Regards,
Andy Shevchenko