From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) (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 9FFB83793D3 for ; Mon, 30 Mar 2026 17:01:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=67.231.153.30 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774890089; cv=none; b=kQKnRKAwCG4gBMwyFMITfeuFnAeiqBT85u+jdI15DfqVi/fmfG8qo4PNWgdntVt/jBqCJlXdFq6lcXtlcwuUCU0R6/N7lHXIB629ioeoQAjuk0zD2AW6WVIlyUsc3d+Y75S6fhnF3OvvAjWt6/2sB0bwBlGHw0Yi3UYixa20QHs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774890089; c=relaxed/simple; bh=5dpj79E3TkNUWGbk/4n3VwDNeI0EzjnkWAvWxRr+Ucg=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=JC0l1vDxSEvaFVyqM5QBx9Tab8Cl1KNxsXk2oMLbRUMY8MXuDFRDbbd1NWNmODd2vDWImOMNnj9nPcB61JIIbVq9QkaYIwDXqECGYbVEPkOaXFAXbhGUg+Rrhfa8afCaFWHyf0ft04bXpHbWpk7PGIQq0lxfond+h4PH0HRellw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com; spf=pass smtp.mailfrom=meta.com; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b=ClKpljK7; arc=none smtp.client-ip=67.231.153.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=meta.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="ClKpljK7" Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 62U3a6IT3368507 for ; Mon, 30 Mar 2026 10:01:26 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=s2048-2025-q2; bh=c+FOvJbopOOU6Ylh/wpHLfBaMAWWNrX6SWR1vtup78M=; b=ClKpljK74dxo kevIdNJuTWFX+l/gW8LHikI7ThkKyi15REQGd7b2EZ8DAJWqxP3sUZOQI6hOr1KR G0uGs2lXs9TJ1pjc9kptnSREU8o7I2JBPFfdUBHzQLmKKmZmlp1vSlkSpbnRratr JCV96E6RAzNoMCrPfyOlkb3PCQUpo/C8GfBenWQP5nmnrVTIJ7G4ZYTYhmvofrJn BMs6OClAtmpGcDh2MlgyIInxrEDjpITifPzOe7prcrs2NM05C++drErkt9sOMYGZ ZIEI1PDMWCfTEKALVHb0tEzIG7sZUXddWv2JmTAPCjLM31852GYa9U7xytVWR4Px 0PJfeBTEoQ== Received: from mail.thefacebook.com ([163.114.134.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 4d6xgexx46-9 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 30 Mar 2026 10:01:26 -0700 (PDT) Received: from twshared10186.03.snb1.facebook.com (2620:10d:c085:208::7cb7) by mail.thefacebook.com (2620:10d:c08b:78::2ac9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.2.2562.35; Mon, 30 Mar 2026 17:01:22 +0000 Received: by devbig197.nha3.facebook.com (Postfix, from userid 544533) id 54FBBDFA0848; Mon, 30 Mar 2026 10:01:16 -0700 (PDT) From: Keith Busch To: , CC: , Keith Busch Subject: [PATCHv4 1/2] dm: initialize dma_alignment to 0 Date: Mon, 30 Mar 2026 10:01:13 -0700 Message-ID: <20260330170114.764606-2-kbusch@meta.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260330170114.764606-1-kbusch@meta.com> References: <20260330170114.764606-1-kbusch@meta.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMzMwMDEzNyBTYWx0ZWRfXxUAQm3teUN8/ mskRG5j55hXDYCvhMdKCg/iOG5YxMmGOnBVab8hQO6A4zYEEYLCulEqSf0sf5Wg4yMMdze0rfvC Z446DUslLV5I87tPrwBv9ZhCUPMfIsGiKPzKLulBiXWQi/UTeN6r76hrtbaploB6E+DUc69bAL8 m5T1e/CGgaXa3PMtcNG7lZ6ftZedtET6MmpM/Mdnxb7A6at8Yd8b5iEi2G2pHvQdqmHqiL2MpXs MYY9bQbMKPPN5Yz0r379r3BC2ZqAXBEUTdueDIfjV8GvYKqBQxgaWctwKJHUtFWTWtCqP5Pq6iA dfwfzRzNA2z0GJCYlE88Aak/JXRF8OriI4hq2sWvminMAflUCq3CDgqU/R8OppthS8izTS1k3zs Svlh1Z5wGfhz4IFzHbEkPT6eS6ttsEdC9LVXdr4Q1FUpkrX63x1cKg56K7MShY/PYG0sGFuidlH 8wTFlvqTbH/TnM4VSuw== X-Proofpoint-GUID: 4ZQb6GviM00W1X_qKpNsUMQP9ktOhPON X-Proofpoint-ORIG-GUID: 4ZQb6GviM00W1X_qKpNsUMQP9ktOhPON X-Authority-Analysis: v=2.4 cv=YcWwJgRf c=1 sm=1 tr=0 ts=69caac66 cx=c_pps a=CB4LiSf2rd0gKozIdrpkBw==:117 a=CB4LiSf2rd0gKozIdrpkBw==:17 a=Yq5XynenixoA:10 a=VkNPw1HP01LnGYTKEx00:22 a=7x6HtfJdh03M6CCDgxCd:22 a=wpfVPzegXHpEFt3DAXn9:22 a=VwQbUJbxAAAA:8 a=Jf3zCm2W71OrLVUcjEQA:9 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-03-29_05,2026-03-28_01,2025-10-01_01 From: Keith Busch All device mappers that want to override the dma_alignment do so. However, because the default stacking limit is set to 511, a device mapper couldn't make it smaller even if it is capable of handling finer grained alignment. Set the default dm stacking dma_alignment limit to 0 so that it can be stacked with any value a device mapper wants. If a mapper doesn't override the value, the initial 0 value will get changed to the original default 511 value when the limits are validated after the device stacking is complete. Signed-off-by: Keith Busch --- drivers/md/dm-table.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index dc2eff6b739df..80326f8096cb7 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -591,6 +591,7 @@ static void dm_set_stacking_limits(struct queue_limit= s *limits) { blk_set_stacking_limits(limits); limits->features |=3D BLK_FEAT_IO_STAT | BLK_FEAT_NOWAIT | BLK_FEAT_POL= L; + limits->dma_alignment =3D 0; } =20 /* --=20 2.52.0