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Date: Sun, 20 Jul 2025 12:26:48 +0200
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Lauri Tirkkonen <lauri@hacktheplanet.fi>
Cc: Mario Limonciello <superm1@kernel.org>, stable@vger.kernel.org,
	regressions@lists.linux.dev, amd-gfx@lists.freedesktop.org,
	Wayne Lin <wayne.lin@amd.com>,
	Alex Deucher <alexander.deucher@amd.com>
Subject: Re: [REGRESSION] [PATCH] drm/amd/display: fix initial backlight
 brightness calculation
Message-ID: <2025072012-deluge-arbitrate-9129@gregkh>
References: <d92458bf-fc2b-47bf-b664-9609a3978646@kernel.org>
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In-Reply-To: <aHy4tohvbwd1HpxI@hacktheplanet.fi>

On Sun, Jul 20, 2025 at 06:36:54PM +0900, Lauri Tirkkonen wrote:
> DIV_ROUND_CLOSEST(x, 100) returns either 0 or 1 if 0<x<=100, so the
> division needs to be performed after the multiplication and not the
> other way around, to properly scale the value.
> 
> Fixes: 6c56c8ec6f97 ("drm/amd/display: Fix default DC and AC levels")

This should be a commit id in Linus's tree, NOT in just one stable
branch.

Also, you forgot to add a cc: stable@vger.kernel.org so that it will be
picked up by a stable release.

thanks,

greg k-h