From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 7D94144D68C; Wed, 21 Jan 2026 07:14:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768979699; cv=none; b=cHJt6l87fS8YWyWGHgbD1HPQi57UTmhwbHBnRvfq2eGY5QIUoAD9HKdCaCCqjbhZVMsIe0CU8RVsxZIbnSsf+nOacSF8OnJUPF60hliqKsN3H7JLZXb8wyEnyZ58Gbch/04znCubh6GPf10OkXAYoY8/rPr1ZXgS9OG75uQOh8E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768979699; c=relaxed/simple; bh=MXPljD5fEgppiCAcWTE+QV4bH88CzPOxUrW5uDUo0fQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ZQ9VcH9qVyeBv2QU6L/ivMY/5S3z/dZpS5HRGNp9TLDj3WIdSvs/H8WTuE5mVwQuaMP3PqSnLfmOTl6KZEc3n5Huz6zaZwa3+fanHAMYqQ4mkGzHCckNzjuNqrFZoseOybgLBAb0IFlqDQMdXSM/udT7mKoSbyTpnZFgA5DzvoA= 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=agU4nZS6; arc=none smtp.client-ip=198.175.65.9 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="agU4nZS6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1768979694; x=1800515694; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=MXPljD5fEgppiCAcWTE+QV4bH88CzPOxUrW5uDUo0fQ=; b=agU4nZS64l1qiEQmLyKqYHxz+IXlJFZatCRiCVPHPprU3fK4sgOhRDJd sTvzLS8TYlQTrqAyHrvCWmJz6+WqEALYUqAuuU/vY4a4Sg2RHhT6Fbucd zqF7WoL90uLvgTRYCSXujz2t4pY6460UASm6Iqs0lCNk1XCYq4PTg5LDu 7cNWI3DKyc/TrkDCNmgnUzZxerS/9xxGHzpSsfSF2wP7WXrEkZ5QS2kha EMEKL30PLL+2E/B6CLh6VqXv/2vC9HSNCbAVJW2JWsG7ffNoHRdEllgTJ y5prcafI2ovrnwL2BoMmDljVSSioI5Y1dkKQLjpBOQxNXGlYIBnShx4VK A==; X-CSE-ConnectionGUID: kbRJF8ApQUGXmRT+CWrl2g== X-CSE-MsgGUID: 2NrX0PS0TGWrXlH/X7gmcg== X-IronPort-AV: E=McAfee;i="6800,10657,11677"; a="92869393" X-IronPort-AV: E=Sophos;i="6.21,242,1763452800"; d="scan'208";a="92869393" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2026 23:14:50 -0800 X-CSE-ConnectionGUID: Hf5YgZrfQ7a9nSf4Yr5/AA== X-CSE-MsgGUID: 7iACQ/imSfGRENC7kimbYw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,242,1763452800"; d="scan'208";a="211227627" Received: from allen-sbox.sh.intel.com (HELO [10.239.159.30]) ([10.239.159.30]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2026 23:14:48 -0800 Message-ID: <3fccd233-c5cf-4252-98ea-61f240f82695@linux.intel.com> Date: Wed, 21 Jan 2026 15:14:42 +0800 Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: IOMMU regression in linux-6.18.y To: Mario Limonciello , Mario Limonciello , regressions , stable@vger.kernel.org Cc: iommu@lists.linux.dev, "Hegde, Vasant" , "Hou, Lizhi" References: <870872aa-28e9-412a-bac6-8020bf560e4f@amd.com> Content-Language: en-US From: Baolu Lu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 1/21/26 13:26, Mario Limonciello wrote: > > > On 1/20/26 8:08 PM, Mario Limonciello wrote: >> Hi, >> >> Recently I found out that amdxdna stopped working in linux-6.18.4. >> This is because of this commit in linux-6.18.y: >> >> commit c341dee80b5d ("iommu: disable SVA when CONFIG_X86 is set") >> >> That was originally backported from upstream: >> >> commit 72f98ef9a4be ("iommu: disable SVA when CONFIG_X86 is set") >> >> --- >> >> SVA support is a requirement for amdxdna. >> >> The series that this commit came from was part of a larger 8 patch >> series, but this was the only commit that was CC'ed to stable. >> >> As a result this is not broken in 6.19-rc, but it is broken in >> linux-6.18.y (and presumably any older stable kernels still around >> that picked it up). >> >> So there are two options I see: >> >> 1) Revert c341dee80b5d in linux-6.18.y (and any other stable kernel >> that picked it up but has amdxdna) >> >> 2) Bring the entire 8 patch series to linux-6.18.y. >> >> This is the entire series (I didn't look up the hashes from mainline, >> but they should have all landed): >> https://lore.kernel.org/linux-iommu/20251022082635.2462433-1- >> baolu.lu@linux.intel.com/ >> >> What should we do? >> > > If the decision is to take the remaining commits to 6.18.y to fix this I > did confirm they cleanly cherry pick and build.  Here are the hashes. > > commit 27bfafac65d8 ("mm: add a ptdesc flag to mark kernel page tables") > commit 977870522af3 ("mm: actually mark kernel page table pages") > commit 412d000346ea ("x86/mm: use 'ptdesc' when freeing PMD pages") > commit 018942956723 ("mm: introduce pure page table freeing function") > commit bf9e4e30f353 ("x86/mm: use pagetable_free()") > commit 5ba2f0a15564 ("mm: introduce deferred freeing for kernel page > tables") > commit e37d5a2d60a3 ("iommu/sva: invalidate stale IOTLB entries for > kernel address space") > Yes. These patches fix a security issue in iommu/sva on x86 and restore the SVA functionality. Thanks, baolu