From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1384CBA3E for ; Tue, 7 Mar 2023 17:36:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6EE18C433EF; Tue, 7 Mar 2023 17:36:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678210606; bh=xLaW9MhnaabbtCXhChoRpKpVK5Vxj2sMJJtHHD3Bago=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TJGfl9Iv8gtJ0ps+1LBSdp/EIMMZ65kx5ZfIiFLWhkmjrNODlZapk2qmT4Q2EmuMa uzMIMuWYt8xancbXG9wXjRD53cLjASbkJQuArOwkeHeA0EYo5FuzD/QuVcBaTOYLJZ tlvBxpZosakCSTOeMlHDgON9RHS56oZJaVFzqocY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Suravee Suthikulpanit , Vasant Hegde , Joerg Roedel , Sasha Levin Subject: [PATCH 6.2 0564/1001] iommu/amd: Do not identity map v2 capable device when snp is enabled Date: Tue, 7 Mar 2023 17:55:36 +0100 Message-Id: <20230307170045.948964158@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Vasant Hegde [ Upstream commit 18792e99ea2fea27c72eb1ecca1879e5e6be304d ] Flow: - Booted system with SNP enabled, memory encryption off and IOMMU DMA translation mode - AMD driver detects v2 capable device and amd_iommu_def_domain_type() returns identity mode - amd_iommu_domain_alloc() returns NULL an SNP is enabled - System will fail to register device On SNP enabled system, passthrough mode is not supported. IOMMU default domain is set to translation mode. We need to return zero from amd_iommu_def_domain_type() so that it allocates translation domain. Fixes: fb2accadaa94 ("iommu/amd: Introduce function to check and enable SNP") CC: Suravee Suthikulpanit Signed-off-by: Vasant Hegde Link: https://lore.kernel.org/r/20230207091752.7656-1-vasant.hegde@amd.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/amd/iommu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 9dc41c48c29d6..ff4f3d4da3402 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2405,12 +2405,17 @@ static int amd_iommu_def_domain_type(struct device *dev) return 0; /* - * Do not identity map IOMMUv2 capable devices when memory encryption is - * active, because some of those devices (AMD GPUs) don't have the - * encryption bit in their DMA-mask and require remapping. + * Do not identity map IOMMUv2 capable devices when: + * - memory encryption is active, because some of those devices + * (AMD GPUs) don't have the encryption bit in their DMA-mask + * and require remapping. + * - SNP is enabled, because it prohibits DTE[Mode]=0. */ - if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT) && dev_data->iommu_v2) + if (dev_data->iommu_v2 && + !cc_platform_has(CC_ATTR_MEM_ENCRYPT) && + !amd_iommu_snp_en) { return IOMMU_DOMAIN_IDENTITY; + } return 0; } -- 2.39.2