From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6BC7C3921CE for ; Tue, 1 Sep 2026 14:07:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788271679; cv=none; b=iu2P10PJjb3p7l22huS9breEixKQDfCuZTVod0FeRbIh85Mh9kgv4ndgTBtFV5IEezlsyly9qSj/YyE2zNpwSjFYiXf1Yz2WqupadXxCl59rHZm0GMRn98npyV9nKTtB1Uy5LlDBYnLkdGhUgI1lmJmE4h1fAgiNhPbduMx9XFE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788271679; c=relaxed/simple; bh=tSjfrdXLdcUvTU5aEDshkad+nAiG/0UiI4xepps565U=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=FYhI2n7Zz5KJX8Ud12bjRetiXTbuuxvd/6koisOiyjr0qC2xRlGqTj/Gg0Aln6bb0R1IIUJ/4+iTLEH6YBTYNiKy8HyTwp+wSgCSqv0uqw3efgr2aKGIdcDY2ikddAYZx/fzB/rLUFTqo0lZvqWCdg86sgerGDGn8s2Dc3Gb3Fw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SpXqayWN; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SpXqayWN" 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 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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