From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (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 A588123C4F3 for ; Fri, 8 May 2026 07:59:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778227201; cv=none; b=uEIqH6gsFcyKoQS11iN7Be9QoyEt1pIOjgjo+/7627t9eM3OhruE6I3lb4rwTLN9jc97Jv7HQ/0PATClI1YbODohPDRzH/+NZhPOD0zlsDO8+M2nfSGvIri6CAw2BCH4b1ZsetxN6qtFDgFAtObCPaGovNOUMoVdJCwvM4j/jN8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778227201; c=relaxed/simple; bh=R5gQPQ1kAWX/k2WrVQv0+R/oHESKRuvWGRRsmzpq3jE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fRvT2AjBqUdpVB32E6cSAh5tXgGKBi1+l3fP/KK/o7+7mPp0HaXRKHr5uUuudM2PFzh+rxdzuuKCM7s7ycD26WOJ4IlxnbZaquY7IU9SZBaMkBoBDZb2M+Mj/qTGG+rUjoebzc97nbRUgv6zMfde2hw9sNT33U/KtYSMcDQBAQY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=C3HYgB7f; arc=none smtp.client-ip=192.198.163.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="C3HYgB7f" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1778227199; x=1809763199; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=R5gQPQ1kAWX/k2WrVQv0+R/oHESKRuvWGRRsmzpq3jE=; b=C3HYgB7fTX/o0tI1Ug3/svY6MAI6/HWVS7jwIXNPFUA8782WZFbmg60W 6Y1M1VMnoG46kxby9tindK3Dvo1IvhSl6amX1BuSxG8zHE3gV4a4IlmxO TDxOjea3ru/YARYS9T3vc1AZRoIWSupPgXMs8AV8uzbqt/GFefwC4RGxP olfJgVxAyjG3RuBiqnjXN43+klZfX4PV1/w8P0K/dZA2Z4tUaLAne5moJ faSDY8QHPs+9lp5F/BhCml4k/9cbuEh+6OVlDv7jexDS/YVzt6ZBqNVi+ NqQv/O3ZVMU2XqHhbJqnUbExGugTw6H083uoudsboPPi+VY821RH8I1KM w==; X-CSE-ConnectionGUID: niqobKIsS0y1DdF+6XQtKQ== X-CSE-MsgGUID: dm+UtTGnTquSAbV+1s19Ig== X-IronPort-AV: E=McAfee;i="6800,10657,11779"; a="90570153" X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="90570153" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 00:59:59 -0700 X-CSE-ConnectionGUID: HbjD7DuVSrKFisCKZ130lw== X-CSE-MsgGUID: +VdyzD4QRUmPsvuxTIUZoQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="241049255" Received: from allen-sbox.sh.intel.com (HELO [10.239.159.30]) ([10.239.159.30]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 00:59:57 -0700 Message-ID: Date: Fri, 8 May 2026 15:57:27 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] iommu/vt-d: Disable DMAR for Intel Q35 IGFX To: =?UTF-8?Q?Naval_Alcal=C3=A1?= Cc: David Woodhouse , Joerg Roedel , Will Deacon , Robin Murphy , "open list:INTEL IOMMU (VT-d)" , open list References: <20260410161622.13549-1-ari@naval.cat> Content-Language: en-US From: Baolu Lu In-Reply-To: <20260410161622.13549-1-ari@naval.cat> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 4/11/26 00:16, Naval Alcalá wrote: > 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. > > This issue has been reported multiple times and remains > unresolved: > Link:https://lore.kernel.org/linux-iommu/20161205215841.GA20819@beast/ > Link:https://bugzilla.kernel.org/show_bug.cgi?id=201185 > Link:https://bugzilla.kernel.org/show_bug.cgi?id=216064 > > Add the missing PCI ID to the existing quirk list to disable > DMAR for this device. > > Signed-off-by: Naval Alcalá > --- > drivers/iommu/intel/iommu.c | 3 +++ > 1 file changed, 3 insertions(+) Queued for v7.1-rc. Thanks!