From nobody Fri Oct 17 10:31:35 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5889CC3A5A1 for ; Wed, 19 Oct 2022 09:31:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233687AbiJSJbX (ORCPT ); Wed, 19 Oct 2022 05:31:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233607AbiJSJ1j (ORCPT ); Wed, 19 Oct 2022 05:27:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0FD03E77A0; Wed, 19 Oct 2022 02:12:21 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id AF9F56185F; Wed, 19 Oct 2022 09:10:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BD6D7C433D6; Wed, 19 Oct 2022 09:10:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666170645; bh=Bl4G7PhvvFyNlas+R2mIUh5HCYKgCqnCPCHdtZQ7cm4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VkSHH1VqtLGq3plhapVtGV+n3lH1O+zSrWbMFhDlFqQbaqskONM6uPnkrvlv0ixp6 zQpeuVKN2+OLWdI7k0XC3H15MvAb1U7QltXqY66Un8be/4Z/LutE3EJpgd8PxduuOU 1npNXgJ2H6bBxg25dlD31cLIo9t2AvetcCdy/8FI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Gow , Tales Aparecida , Alex Deucher , Sasha Levin Subject: [PATCH 6.0 733/862] drm/amd/display: fix overflow on MIN_I64 definition Date: Wed, 19 Oct 2022 10:33:40 +0200 Message-Id: <20221019083322.330191882@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Gow [ Upstream commit 6ae0632d17759852c07e2d1e0a31c728eb6ba246 ] The definition of MIN_I64 in bw_fixed.c can cause gcc to whinge about integer overflow, because it is treated as a positive value, which is then negated. The temporary positive value is not necessarily representable. This causes the following warning: ../drivers/gpu/drm/amd/amdgpu/../display/dc/dml/calcs/bw_fixed.c:30:19: warning: integer overflow in expression =E2=80=98-9223372036854775808=E2=80= =99 of type =E2=80=98long long int=E2=80=99 results in =E2=80=98-9223372036854775808=E2= =80=99 [-Woverflow] 30 | (int64_t)(-(1LL << 63)) | ^ Writing out (-MAX_I64 - 1) works instead. Signed-off-by: David Gow Signed-off-by: Tales Aparecida Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/dml/calcs/bw_fixed.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dml/calcs/bw_fixed.c b/drivers/= gpu/drm/amd/display/dc/dml/calcs/bw_fixed.c index 6ca288fb5fb9..2d46bc527b21 100644 --- a/drivers/gpu/drm/amd/display/dc/dml/calcs/bw_fixed.c +++ b/drivers/gpu/drm/amd/display/dc/dml/calcs/bw_fixed.c @@ -26,12 +26,12 @@ #include "bw_fixed.h" =20 =20 -#define MIN_I64 \ - (int64_t)(-(1LL << 63)) - #define MAX_I64 \ (int64_t)((1ULL << 63) - 1) =20 +#define MIN_I64 \ + (-MAX_I64 - 1) + #define FRACTIONAL_PART_MASK \ ((1ULL << BW_FIXED_BITS_PER_FRACTIONAL_PART) - 1) =20 --=20 2.35.1