Re: [PATCH 13/13] interconnect: mediatek: Aggregate bandwidth with saturating add
From: AngeloGioacchino Del Regno
Date: Mon Nov 17 2025 - 07:50:14 EST
Il 14/11/25 17:54, Nicolas Frattaroli ha scritto:
By using a regular non-overflow-checking add, the MediaTek icc-emi
driver will happy wrap at U32_MAX + 1 to 0. As it's common for the
interconnect core to fill in INT_MAX values, this is not a hypothetical
situation, but something that actually happens in regular use. This
would be pretty disasterous if anything used this driver.
Replace the addition with an overflow-checked addition from overflow.h,
and saturate to U32_MAX if an overflow is detected.
Fixes: b45293799f75 ("interconnect: mediatek: Add MediaTek MT8183/8195 EMI Interconnect driver")
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@xxxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>