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 51D1C3AE6F7; Wed, 21 Jan 2026 05:26:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768973178; cv=none; b=mGvSnFHm90Zspkm6mXsnW4A7Ln3nKvfUOwj+8ozD8OAf5TGz0eEN7XMI0uoq1jlBLOTtoNdFEwAvp0/8kUxx+dmgYh1S2wEumhEZ4E3Hvf/K2Vvm/olrDUMaNgqAvcbMIFpaTwvjrmIVjMbdx3S5ScV4Qt4SUHq/g8rUtdNhINY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768973178; c=relaxed/simple; bh=RDkIzU1M1GBUXwDEehGXspAVBhm6BfIX4T89ZMX1nb8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=WD1u+GhP0oeTRfi0KiHLERbZArAcUKicI7U/0pOO9vOdD46aixmAZbgSqJAF+enA2H521N8taDpaMbuExqvj1rHydtgpC60+rCkuxOc2k+Vi9WuQRmkVAPp+peDnj6sZqartmSRKkLFCXIeOTdusy7S/ikjSowmh0uiUBjLPhxI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h55vB+Ep; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="h55vB+Ep" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50AC6C116D0; Wed, 21 Jan 2026 05:26:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768973177; bh=RDkIzU1M1GBUXwDEehGXspAVBhm6BfIX4T89ZMX1nb8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=h55vB+Epr+eJT5v0DdOeqotnGiueC8jmHAlr+A3mLZXuTIpBxaaRoYN0MLQqHroIe 24vON2zNIlaYqRMr0O0kYDPbgvfY27eMyEev5vGwFieTtbfu2H5iFRc6MW9XZ7G/7Y hUkiGvjZxsu69XwX390bVcbBhBOA0Z9lxQFrunOiY3bfYgg2JGZsbpKherUb7VEb0I 4KsVH3jttxI4CqRypmpCL3+hmkiRG01Eh30JvCsd22KdO+AxaIDw7gjtRmztd93+D7 soev5ydrVTK3XdFB8wY/OhLX/RJxHuANaa03u8PGz0KPn46nKHdwJa8Her2m2uawPr duoJi2mkqTvng== Message-ID: Date: Tue, 20 Jan 2026 23:26:16 -0600 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 , 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: Mario Limonciello In-Reply-To: <870872aa-28e9-412a-bac6-8020bf560e4f@amd.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 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")