From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f66.google.com (mail-wr1-f66.google.com [209.85.221.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C88C7207A38 for ; Mon, 5 Jan 2026 09:52:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.66 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767606725; cv=none; b=sj8iFUnDtUjEGdmFdr9cH7g3UPn9FPWJQunhdm797Lg5cPxaD0uKJHPwXvAFcHhMtVIUWcm3YCpvUltMvn+eO8cKjJ2rNySmVwSxRpMpwTbSNT7KmFwRwEHhzK0wZttNALdaPa7DfiCV6YoTFJMLP+AVjaEdX0joPkuPU9LkOZQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767606725; c=relaxed/simple; bh=5ejwvdViHGpZahmzeANBNrpoCx269JspGOeia0IssR8=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Fqe3G4rlfwOWccAJn/nSEP1A7opR67hTbV9q9nLiIbV1neMFVQAjh8cXN7mEsQiXSLaQap+h0kQKdLKsSzw8YLqBSo5CJmj/IvARtSK1czUcq66rf1FzvmFFy+AUUV+4mUFjtDX5OqtRohaSs5wMwdVGx1Z10uGNmcb5qoPwwY4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=aV+pbrxL; arc=none smtp.client-ip=209.85.221.66 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="aV+pbrxL" Received: by mail-wr1-f66.google.com with SMTP id ffacd0b85a97d-42fbb061a08so815127f8f.2 for ; Mon, 05 Jan 2026 01:52:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1767606721; x=1768211521; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=txMxKLJCIQFzStXgaX6zCY9uCsyn60vWSct+HXcfqZM=; b=aV+pbrxLsU59nomiUoyHoMhTzgrzQcb4kYd4Ns0BW40XPkU+maHVDcUkxv43DfZQUt SGD4SjU6ieEnpW3QEKvmKgH/5b4mcvV0DtqzIFw5AVBZh1MsL0VZXIZcO7ofeexiwYoc ZAcdWngFFHTclnSVB048z68z1Axl0NsiXG0emFd0VFSg408K6X2rfcTKoUM1NHFdW003 dXRUA74v9Slkcjd49LZtZRxKGtBVaJzNvWxIct8y5h4++fO19q8+WmWz57Fny792Yrw/ R4ByhgWg5cyvbrqW5+m61OAQmFb2TIkgC1S3vpQG+yJT1XQMNEZOirSvag2Ngltp04Ey aijQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767606721; x=1768211521; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=txMxKLJCIQFzStXgaX6zCY9uCsyn60vWSct+HXcfqZM=; b=d56VldqHsc39+IsTdqM+1mby3nxCCj5HW37P5I8PGItMy0ENz4nik2PEFoWGwWp7hA O+i8m6wydoSRuozEsDjQy1FPl+movJkcBJyNxFKVIbhphFNq5X+6MGYDCc7OKKItU77d 49f+JGC8GCzDuThZnzI3BTdDcyl5CgohKfwEiOJGXBrip166yqJiutL/roP0leFbgnNa b3VLiveICwPSRK6nakjLQZXLLEkg1Gcu6j+vCv/mqOk4g8HlMHKDxP/ujXh9qJU/JFau jUGtj3FIqSfbZV5FPEqWqL6E5jCc8RMVspNmT4Gc5pT1lgLyDkEXNM+UAQsJnhNXsQeG d7uw== X-Forwarded-Encrypted: i=1; AJvYcCWn9ISZE35YgAqLEFuInbl0hX4qW6BVqpbmhPN1x7PPpWGTEqoXYhhyoIhXkHRsOTRDQPkrNQfmyVecSWA/Jg==@lists.linux.dev X-Gm-Message-State: AOJu0YwvWjvW615y7mbl/Vz+Oo1Pv5vinCGwER0xLfb1PZO+of2oFviT 1NlPAp5UV9Td8ODBbyKPjSRJjIaJmCh0NbjMCo8VOJm2013zq/EoGnw7pCZ+zMLyxWY= X-Gm-Gg: AY/fxX4kkcxXvc+RHxCkKVdaCzvFy9h/UeKAE+B1uyRhA9S0yOYxysKcZl06i5Bh7gx MbdSsuWWcumpsts/DQPYe0Yhhn3Q2dslGFsnkxxV7UZVzgfOgb96eZpkJYwYwS54ZC5NnYs9APb yVprCcH47S9WgP7kXl3jzASIU+0ZksJdrRJa/83E7EA5wf6eXDlmT+1Ilajs/lVWOHemFdGvrK3 NiyIwrNSiH+TAsqlEZoR/VkiPYVEQ7ojW8kaGRXkkr+lLGCcR1hwnRMjtOwNuvxKJgA4VE/wGuI KA9RDjVs4jwDcwrKjWoEDF/tZAkM9wjiD/lyikLa8qvHFU0fbk2N1Jq4V02xdcoguWXDQJ/iz4H Gl/pU/W9mWNgkb5TtCmVJiHSvS4gtpG/Bmj/L81rCCww04+lB1+G4n3RZK8+j7B/G5UqJenB9OS dejMzYY08tk3RD4Vq/L64G5F1wuBBDdZZ4vl0fub5TT1BO4qp8BLZ2dioKrrIWO/5e/MLCuJS3c Ast X-Google-Smtp-Source: AGHT+IG/wqgOkqwXrB1rsCOv37yZ5+KfBZKuhJz5pDuTeJ4oXS1iaQsQoWFexgrkxGoC7pycuuDd5g== X-Received: by 2002:a05:6000:2305:b0:429:cf2b:cb0a with SMTP id ffacd0b85a97d-4324e4bf220mr35541794f8f.2.1767606721058; Mon, 05 Jan 2026 01:52:01 -0800 (PST) Received: from mordecai (dynamic-2a00-1028-83b8-1e7a-3010-3bd6-8521-caf1.ipv6.o2.cz. [2a00:1028:83b8:1e7a:3010:3bd6:8521:caf1]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4327778e27bsm66263511f8f.12.2026.01.05.01.51.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jan 2026 01:52:00 -0800 (PST) Date: Mon, 5 Jan 2026 10:51:58 +0100 From: Petr Tesarik To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, Cong Wang , Jonathan Corbet , Olivia Mackall , Herbert Xu , Jason Wang , Paolo Bonzini , Stefan Hajnoczi , Eugenio =?UTF-8?B?UMOpcmV6?= , "James E.J. Bottomley" , "Martin K. Petersen" , Gerd Hoffmann , Xuan Zhuo , Marek Szyprowski , Robin Murphy , Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Leon Romanovsky , Jason Gunthorpe , Bartosz Golaszewski , linux-doc@vger.kernel.org, linux-crypto@vger.kernel.org, virtualization@lists.linux.dev, linux-scsi@vger.kernel.org, iommu@lists.linux.dev, kvm@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH v2 04/15] docs: dma-api: document DMA_ATTR_CPU_CACHE_CLEAN Message-ID: <20260105105158.248b4dd2@mordecai> In-Reply-To: <0720b4be31c1b7a38edca67fd0c97983d2a56936.1767601130.git.mst@redhat.com> References: <0720b4be31c1b7a38edca67fd0c97983d2a56936.1767601130.git.mst@redhat.com> X-Mailer: Claws Mail 4.3.1 (GTK 3.24.51; x86_64-suse-linux-gnu) Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 5 Jan 2026 03:23:05 -0500 "Michael S. Tsirkin" wrote: > Document DMA_ATTR_CPU_CACHE_CLEAN as implemented in the > previous patch. > > Signed-off-by: Michael S. Tsirkin LGTM. I'm not formally a reviewer, but FWIW: Reviewed-by: Petr Tesarik > --- > Documentation/core-api/dma-attributes.rst | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/Documentation/core-api/dma-attributes.rst b/Documentation/core-api/dma-attributes.rst > index 0bdc2be65e57..1d7bfad73b1c 100644 > --- a/Documentation/core-api/dma-attributes.rst > +++ b/Documentation/core-api/dma-attributes.rst > @@ -148,3 +148,12 @@ DMA_ATTR_MMIO is appropriate. > For architectures that require cache flushing for DMA coherence > DMA_ATTR_MMIO will not perform any cache flushing. The address > provided must never be mapped cacheable into the CPU. > + > +DMA_ATTR_CPU_CACHE_CLEAN > +------------------------ > + > +This attribute indicates the CPU will not dirty any cacheline overlapping this > +DMA_FROM_DEVICE/DMA_BIDIRECTIONAL buffer while it is mapped. This allows > +multiple small buffers to safely share a cacheline without risk of data > +corruption, suppressing DMA debug warnings about overlapping mappings. > +All mappings sharing a cacheline should have this attribute.