From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f48.google.com (mail-wm1-f48.google.com [209.85.128.48]) (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 631153EFFCE for ; Tue, 2 Jun 2026 14:25:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.48 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780410321; cv=none; b=qUHr9DSAY7Dkhf7eQqJClkR0iTem0pQ47gfpSrgy3qOBrMlxKo8dX/RmCEowPZ7Xx44ENRGxAxLtL7U3XOeSilis8EESMK73fw1a7iv70uQMj6+8Gg8cIJw9r0kzBAqAA6OWVqmRU0ECaWHEeToK/HDLqSMNN8Y25aeU0buGvu0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780410321; c=relaxed/simple; bh=7c3By5Fqf6YUXX91bObyQOTRnp7RUJa/336wDuuAYVo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Sl4YJ1stiypIiN84zFtJwoJCs1Lqe9HK2jYvdM5NWv2HkG7ppckRWWRP3bOwbsLEQ1yhqHdTCP3UxjmVF8eVIrFmgZMYqUZHXuCfqAPURWCXjnv1ULnkR3FLuMf6c6AjDElG+DZmUVEhZQ9baSiMiyE9GaoL2cNz+G89aFeV+38= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=HznJK6c0; arc=none smtp.client-ip=209.85.128.48 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="HznJK6c0" Received: by mail-wm1-f48.google.com with SMTP id 5b1f17b1804b1-49045e2a8a2so1105e9.0 for ; Tue, 02 Jun 2026 07:25:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780410319; x=1781015119; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=o9oIfSe8SaoV8fiGTSV1jg9fuPB2TzAWTv2+N73dZ3o=; b=HznJK6c013S0H42f+Qqj3b1RzmFZV3CvKQDKMRt94un62vgeJNQ/r7lvjqBa6xTLvn bJbmF+dReHT4eJjRZaExjM4klSPaal7Mlgd07sNEtQwdq4qRmokoUBeLlvfUdRywSp0y oJVzVpJBBjnOs95QJz1xp6rSeHMCpWdfS930QXvHUJ4eT/6yrZr08xpENzlxLqEb40NA emLJbcRmgh9PMZ/ejODWVinDveXOOweqqXIoWVmlB3lywVFRqQw4goDsg+tGubzlDvN4 DbN8RIGQVqU7bwC7iUHmdkix9zRjSZ/UIE7JjeEuVvNCP9K2BcMML4YIzjlWZ1Dk39i9 JhAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780410319; x=1781015119; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=o9oIfSe8SaoV8fiGTSV1jg9fuPB2TzAWTv2+N73dZ3o=; b=tLzV9mnSHgQvhhhcY+IrB4G2dyLqK4396dNJ0Z+hGEvHFfrMB8Yf2XOwbKS/ssiS67 tbVqow+e2eK3mtKfxl2fkVHNT9im/EBP2EMehJKRhYOfkxSLif0ImMVqB8y31ZpNQq3a T9SkMgqdUL54Cul+7djKTNSjU5jMbkzCNKFfutp6MggPaJ3i/sIJgBQYKFvrRBOp4W7W gTQelbfO0UTw5ZOtg9TbggNudZj7fhjtHoSzKubLQxdJQ7kYojddAJHBjZp0AkRofZtE qhIngEl/doayGm9y6NlLENyhpvUvVruvL+9adilczoSD0T5Xtdnbt7K/17200jf528z1 i7Qg== X-Forwarded-Encrypted: i=1; AFNElJ9kbcCQQgrwtL5bERDjAM9xpgsEc1vS1r1C/bcyG9P+qBpnFEwW1SKEi/leZkNj3t1mmXBrj1DYD5E5s70=@vger.kernel.org X-Gm-Message-State: AOJu0YzhHy5MX13avjbM/hY7g9nOFKUaJ4M/JLLE3Av6zPPqBhI0jg6o T8IYi+1VSgV0n31C2AUPa3++mEM08milQ9aVfPUuQUol59PcWcO+qmfRTYDFmxugQp/4k36eG/p 8Bix0pw== X-Gm-Gg: Acq92OG3qm2wFX3ZekjM2pqJHVIcRUYoHHNWlf7cKloQ/ypQPhkkzpJQBDuLETVewyn Qo5BpQ6bEsYqB70NpzJg25hdCmZu/Lp7bg+HFVkbafyXKhI1yWneHinpXXnG44YX7Qd6X1Dh99V a/nKd+yzb/Kd9AHWRIwXSx84zU4K6ANh2mZOwvi8pHaxWBOHllOhmFYyl0DuaNZDEUhbX5Iqciq CarJhEss/N6LXxUmltEZdREF+ZT+MZJHdZCUA1PyeTaSkcefdIyQxT0+gmi/jKfK/XYYNVqgoc4 FgORve1mE/ITgiY5EcviwN2e5zvgj3B9yqD6Qx7BNKoL3mZv5XC4kQk8O/e12MksAOzSVZljTgT pyZnnuLgz64/9otiRJaweqLhoYs5WH6vJOxonrUQHvSm8BgwCbNKaB4BgScl21il7PiF+XNcjCn zGCWQPV7QItcYctNmdYfgUMrzZVvfatCPllttYULUR2BMGFhCA24nGNmZGupxWPHuQ5/paLDYT X-Received: by 2002:a05:600c:2203:b0:490:b4bb:21e with SMTP id 5b1f17b1804b1-490b4bb0331mr153245e9.1.1780410317170; Tue, 02 Jun 2026 07:25:17 -0700 (PDT) Received: from google.com (203.80.140.34.bc.googleusercontent.com. [34.140.80.203]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-490b0e18e1csm66666745e9.4.2026.06.02.07.25.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Jun 2026 07:25:16 -0700 (PDT) Date: Tue, 2 Jun 2026 14:25:12 +0000 From: Mostafa Saleh To: "Aneesh Kumar K.V (Arm)" Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, robin.murphy@arm.com, m.szyprowski@samsung.com, will@kernel.org, maz@kernel.org, suzuki.poulose@arm.com, catalin.marinas@arm.com, jiri@resnulli.us, jgg@ziepe.ca Subject: Re: [PATCH v2 0/8] dma-mapping: Use DMA_ATTR_CC_SHARED through direct, pool and swiotlb paths Message-ID: References: <20260420061415.3650870-1-aneesh.kumar@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260420061415.3650870-1-aneesh.kumar@kernel.org> On Mon, Apr 20, 2026 at 11:44:07AM +0530, Aneesh Kumar K.V (Arm) wrote: > This series propagates DMA_ATTR_CC_SHARED through the dma-direct, > dma-pool, and swiotlb paths so that encrypted and decrypted DMA buffers > are handled consistently. > > Today, the direct DMA path mostly relies on force_dma_unencrypted() for > shared/decrypted buffer handling. This series consolidates the > force_dma_unencrypted() checks in the top-level functions and ensures > that the remaining DMA interfaces use DMA attributes to make the correct > decisions. I tested this series on protected KVM and did not see regressions. Tested-by: Mostafa Saleh Next, I will: - Send the pKVM CC patch separately. - Review this series. Thanks, Mostafa > > The series: > - moves swiotlb-backed allocations out of __dma_direct_alloc_pages(), > - propagates DMA_ATTR_CC_SHARED through the dma-direct alloc/free > paths, > - teaches the atomic DMA pools to track encrypted versus decrypted > state, > - tracks swiotlb pool encryption state and enforces strict pool > selection, > - centralizes encrypted/decrypted pgprot handling in dma_pgprot() using > DMA attributes, > - makes dma_direct_map_phys() choose the DMA address encoding from > attrs, and > - uses the selected swiotlb pool state to derive the returned DMA > address. > > Changes from v1: > * rebased to latest kernel (change from DMA_ATTR_CC_DECRYPTED -> DMA_ATTR_CC_SHARED) > * Update alloc path such that DMA_ATTR_CC_SHARED s not a caller-visible attribute. > > Aneesh Kumar K.V (Arm) (8): > dma-direct: swiotlb: handle swiotlb alloc/free outside > __dma_direct_alloc_pages > dma-direct: use DMA_ATTR_CC_SHARED in alloc/free paths > dma-pool: track decrypted atomic pools and select them via attrs > dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED > dma-mapping: make dma_pgprot() honor DMA_ATTR_CC_SHARED > dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED > dma-direct: set decrypted flag for remapped DMA allocations > dma-direct: select DMA address encoding from DMA_ATTR_CC_SHARED > > drivers/iommu/dma-iommu.c | 2 +- > include/linux/dma-direct.h | 10 ++ > include/linux/dma-map-ops.h | 2 +- > include/linux/swiotlb.h | 7 +- > kernel/dma/direct.c | 185 ++++++++++++++++++++++++++++-------- > kernel/dma/direct.h | 25 ++--- > kernel/dma/mapping.c | 16 +++- > kernel/dma/pool.c | 154 +++++++++++++++++++----------- > kernel/dma/swiotlb.c | 89 +++++++++++++---- > 9 files changed, 355 insertions(+), 135 deletions(-) > > > base-commit: c1f49dea2b8f335813d3b348fd39117fb8efb428 > -- > 2.43.0 >