Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 8C0B93C870E; Wed, 20 May 2026 17:14:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297284; cv=none; b=rGau1YIP8UCpR9QDqfFk9bxesH7U9o5xej9Nu46Jx2pylCl/qrpb5/AkiTc4CX86BECDrqOSs6R6rpic0mnypEpzBcKh5HMjOv6fidX8vm7fZWRepSeWyfOD1cF5Kk6Wrtc7SF8wZSroeQSlEPPNlywl6zU01LbU2QeL69qfa/w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297284; c=relaxed/simple; bh=A1e8HRbJbTvjA8vg8dh1BcVkJESUxJrpoHk3OWgZVO4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=acPunJ6xMbEajc0vf8Dsu+rfKnJAfYQQqqR3Ru/my9IDC347ZuOXPNxJty43TLzxVnW+4ewM2HRS5bjJvbouLTm8bQkoGVgcLfkd0DsKqPMUr+cfSyP3TWvSWDhclxc6VDz3L0wG6XOyXlbnXvJZtmlSzNDhoU7VjQcAOC0ui/0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HaXRq3tk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HaXRq3tk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F31E41F000E9; Wed, 20 May 2026 17:14:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779297283; bh=7h6eBglBVaO8Df/MOH246y7HhrVDmFaBBTBE3wNM30M=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HaXRq3tkciN1lCR91bd5FOQHLkrOr9hS8L6Aerm9+254SACNXRYjdBXLnj6QCtQt6 SPrHKKG9XHwJt8YqB0JF6+Jw6EneLVmm77kRTHjGJWnzepQnZh7NcKvWRzaSF8oqFZ +jq4Thp+8Z9vHMi7dvczUM1s1RGYoWkzVQn1vbz8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Naval=20Alcal=C3=A1?= , Lu Baolu , Joerg Roedel Subject: [PATCH 7.0 1119/1146] iommu/vt-d: Disable DMAR for Intel Q35 IGFX Date: Wed, 20 May 2026 18:22:49 +0200 Message-ID: <20260520162213.566647051@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162148.390695140@linuxfoundation.org> References: <20260520162148.390695140@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore 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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Naval Alcalá commit 2cda2e10dc8343ae01eae9e999a876b7e7d37861 upstream. Intel Q35 integrated graphics (8086:29b2) exhibits broken DMAR behaviour similar to other G4x/GM45 devices for which DMAR is already disabled via quirks. When DMAR is enabled, the system may hard lock up during boot or early device initialization, requiring a reset. Add the missing PCI ID to the existing quirk list to disable DMAR for this device. Fixes: 1f76249cc3be ("iommu/vt-d: Declare Broadwell igfx dmar support snafu") Cc: stable@vger.kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=201185 Closes: https://bugzilla.kernel.org/show_bug.cgi?id=216064 Signed-off-by: Naval Alcalá Link: https://lore.kernel.org/r/20260410161622.13549-1-ari@naval.cat Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/intel/iommu.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -3933,6 +3933,9 @@ static void quirk_iommu_igfx(struct pci_ disable_igfx_iommu = 1; } +/* Q35 integrated gfx dmar support is totally busted. */ +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x29b2, quirk_iommu_igfx); + /* G4x/GM45 integrated gfx dmar support is totally busted. */ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2a40, quirk_iommu_igfx); DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2e00, quirk_iommu_igfx);