From mboxrd@z Thu Jan 1 00:00:00 1970 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B2190C624D4 for ; Tue, 1 Sep 2026 14:07:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EE5FC10ED15; Tue, 1 Sep 2026 14:07:58 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="SpXqayWN"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id C4C3710ED0D; Tue, 1 Sep 2026 14:07:57 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 9B89741A73; Tue, 1 Sep 2026 14:07:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A6C51F000E9; Tue, 1 Sep 2026 14:07:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788271677; bh=dOFHe9qy1FZ9AF7sT7V/8hJAwDE8aQjo4Sa9CzpQyek=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=SpXqayWNt+PO/X6NDg09ZCcJ7lHRUQ/2K46HBjqYSObsNhAQptkcFYcbB6YEvLbFF kNK6Ci3Ls4HI8VXFRbDxa/TL7v4SKF4170GWynJ7a+Idu7Ofz+tioACRnAQlMtKrxX pdEPo6Vikx4ZKHGsXA4h6RcG1vyoDFl6LAwpSdw9ghO/GBDZNNdMQPCNd0SrPCfR2C soWF9BoDtgFC+7RKtccvM4lG2iWvCWV6JdHvVqUtsf+QvN9QJK2vxFlnyI5Anmhfu1 WiybX0lRfZSAeoFgTHjDphX/6qLBX9Z6jrgspOGZpPBxDnDSaIp5Fo1DDddItnjOjT 0owUZHSaKERJQ== Message-ID: <8cb96c08-2d1e-459e-b356-c6fd97ef869e@kernel.org> Date: Tue, 1 Sep 2026 16:07:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] drm/nouveau: Use write-combined maps for coherent To: webgeek1234@gmail.com Cc: Lyude Paul , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org, Faith Ekstrand References: <20260821-tegra-coherent-wc-v2-1-2b1ddb67bf18@gmail.com> From: Danilo Krummrich Content-Language: en-US In-Reply-To: <20260821-tegra-coherent-wc-v2-1-2b1ddb67bf18@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 8/22/26 6:42 AM, Aaron Kling via B4 Relay wrote: > From: Faith Ekstrand > > On Tegra devices, uncached maps traslate to device memory, causing > unaligned accesses by userspace resulting in a SIGBUS. Instead, use > write-combined maps to ensure proper access. > > This would also affect discrete cards on any Arm device. It was > determined that discrete cards regardless of cpu arch should use > write-combined maps for coherent anyways. Thus this change is made for > all gpu types. > > Signed-off-by: Faith Ekstrand > Co-developed-by: Aaron Kling > Signed-off-by: Aaron Kling Can you please provide a Fixes: tag? Also, please remember to Cc: stable if necessary. Thanks, Danilo