Re: [PATCH 1/2] remoteproc: mediatek: Make sure IPI buffer fits in L2TCM - Tzung-Bi Shih

From: Tzung-Bi Shih <tzungbi@kernel.org>
To: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: mathieu.poirier@linaro.org, andersson@kernel.org,
	matthias.bgg@gmail.com, tinghan.shen@mediatek.com,
	linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org, wenst@chromium.org,
	kernel@collabora.com
Subject: Re: [PATCH 1/2] remoteproc: mediatek: Make sure IPI buffer fits in L2TCM
Date: Fri, 22 Mar 2024 14:16:34 +0800	[thread overview]
Message-ID: <Zf0iQikMyerbWVMG@google.com> (raw)
In-Reply-To: <20240321084614.45253-2-angelogioacchino.delregno@collabora.com>

On Thu, Mar 21, 2024 at 09:46:13AM +0100, AngeloGioacchino Del Regno wrote:
> The IPI buffer location is read from the firmware that we load to the
> System Companion Processor, and it's not granted that both the SRAM
> (L2TCM) size that is defined in the devicetree node is large enough
> for that, and while this is especially true for multi-core SCP, it's
> still useful to check on single-core variants as well.
> 
> Failing to perform this check may make this driver perform R/W
> oeprations out of the L2TCM boundary, resulting (at best) in a
> kernel panic.
> 
> To fix that, check that the IPI buffer fits, otherwise return a
> failure and refuse to boot the relevant SCP core (or the SCP at
> all, if this is single core).
> 
> Fixes: 3efa0ea743b7 ("remoteproc/mediatek: read IPI buffer offset from FW")
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>