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b=h0nXSzBWR6HagxqLQQxExcdCA41U2Ckyr5EJDcO7HSz7Kjr3KH7E9HIBpBZqm1iLYjOVYzIs+JMblS1N1YU6TZ/OGorGnigaKQx3GnDmyj2Cy08cC8SreyHyRJCgD/QjtGMBUi5njkXMtV2Po13KfObQDS2yX3TYqYTDhZGcvGs= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from BL4PR12MB9505.namprd12.prod.outlook.com (2603:10b6:208:591::16) by MN2PR12MB4222.namprd12.prod.outlook.com (2603:10b6:208:19a::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.406.9; Fri, 11 Sep 2026 04:27:08 +0000 Received: from BL4PR12MB9505.namprd12.prod.outlook.com ([fe80::73aa:eb8c:a86b:5a83]) by BL4PR12MB9505.namprd12.prod.outlook.com ([fe80::73aa:eb8c:a86b:5a83%5]) with mapi id 15.21.0406.007; Fri, 11 Sep 2026 04:27:08 +0000 Message-ID: <97f230ec-89f2-4538-b8c7-55534f94d821@amd.com> Date: Fri, 11 Sep 2026 09:56:59 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 2/4] iommu/amd: Remove iommu_ignore_device() To: Pranjal Shrivastava , iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Joerg Roedel , Will Deacon , Suravee Suthikulpanit , Ankit Soni , Jason Gunthorpe , Bjorn Helgaas , Samiullah Khawaja , sashiko-bot@kernel.org References: <20260910142655.3281464-1-praan@google.com> <20260910142655.3281464-3-praan@google.com> Content-Language: en-US From: Vasant Hegde In-Reply-To: <20260910142655.3281464-3-praan@google.com> Content-Type: text/plain; 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During normal boot, DTEs start out unconfigured (blocking DMA), making > clearing redundant. > 2. During kdump boot, pre-existing translations should be kept running > until deferred attach rather than abruptly clearing them, which risks > breaking in-flight transfers. > 3. Writing to the DTE table via memset without flushing the hardware DTE > cache risks aliasing & torn writes. > 4. Clearing the rlookup_table entry breaks interrupt remapping for > devices that fail probe or operate in translation-less modes. > > Remove iommu_ignore_device() entirely and simplify the error return > paths in amd_iommu_probe_device(). > > Suggested-by: Jason Gunthorpe > Suggested-by: Vasant Hegde > Reported-by: sashiko-bot@kernel.org > Closes: https://lore.kernel.org/all/20260529153216.2AD1E1F00899@smtp.kernel.org/ > Signed-off-by: Pranjal Shrivastava Reviewed-by: Vasant Hegde -Vasant