From mboxrd@z Thu Jan 1 00:00:00 1970 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 E41DB1A9F96; Mon, 12 Oct 2026 20:19:12 +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=1791836354; cv=none; b=qeCWk/ibC8M3CqL23povNc12CK31OY5HkntjbMfV+u7SSjneY1hSacBcNm187N7b2llVOqAMQA/l2quhNTih3ujGNmwya7U9TtdOhzk8t6PtrepQEVVTI9SgPVfx/q/ZE10DpO/4Cg3u0hIz+fqheriLYj08PLFqUZXl3Ath1lo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791836354; c=relaxed/simple; bh=qU4s39QXYGF6y387WXktHtZDr51vM9T/ExPWCcqhXy0=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=dMOyfj9LYPgNbRiesyDTHM5f5vfYVWzuUM6WEP6ehoQwzLWI/O78VhmHmDoIrKThFfvSRMiRpoR58xo1s73HAXD6eNkj3f9MiBJE0GVcJuBIzXZFTZhir10u2gtv4hT9hbf+Ng31TTKkMOJBcoy+/OFwju4MRPXecv4ygDbpXQE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PdPnoYHq; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PdPnoYHq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B4851F0089B; Mon, 12 Oct 2026 20:19:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791836352; bh=f9BkgVVYBdq6Ts9SUFvsw/7XFAECAP2nrcXtcKnMv2E=; h=Date:From:To:Cc:Subject:In-Reply-To; b=PdPnoYHqZnuCaHu+l29sLiHgVnChMLNTvXt+WIP/DYueKP+44Z6Jt5gCgou/RFFlY YsQ6jAsyoB4TnXdybb9yeBkzRvGB77ZvX1n6N23a6bCMH9cO5Cp9LpWEjc3bp+OMsm bmKJlz8PoR9bu1G5SvWzYuu1fHh+T03ZSGWUsK+BtNPHBaP7Wt7SOqkWd6veSacjAO cDeKKJz8GQjvjICy3CLqU+SN7FNKVYW/pUXPIlyUZxZ5YzowzwGlKf2xWioWJAudVm 6P2xtamffQ+jhr+8ADNFkhTetins4X5SQLdi3bCCowwuYAP3rAjIm7VQf8E7ODqNfT hmavqpwSVbcuA== Date: Mon, 12 Oct 2026 15:19:10 -0500 From: Bjorn Helgaas To: Varsh Satti Cc: Rickey Bartlett , Nirmal Patel , Jonathan Derrick , Lorenzo Pieralisi , Krzysztof Wilczynski , Kai-Heng Feng , Keith Busch , Manivannan Sadhasivam , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: vmd: Flush initiator posted writes before demuxing interrupts on Meteor Lake Message-ID: <20261012201910.GA1379657@bhelgaas> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261012194011.48215-1-varsh@varram.me> On Mon, Oct 12, 2026 at 02:40:11PM -0500, Varsh Satti wrote: > On Mon, Aug 24, 2026 at 09:32:20PM -0700, Rickey Bartlett wrote: > > Meteor Lake VMD (8086:7d0b) is affected by erratum MTL016: the VMD can > > signal its MSI before the posted writes carrying a child device's DMA > > data have landed in memory. > > Arrow Lake-H is affected too. It uses the same VMD device ID > (8086:7d0b), so the existing match already covers it. > > Hardware: ASUS ROG Zephyrus G16 GU605CP (BIOS GU605CP.307), Core Ultra 9 > 285H, with a WD PC SN5000S (firmware 34230100) as the only device behind > the VMD. > > Without the patch, on 7.2.9, I got 13 "timeout, completion polled" > events in about an hour of desktop use. Each one froze the desktop for > up to 30 seconds. Disabling APST and ASPM > (nvme_core.default_ps_max_latency_us=0 pcie_aspm=off) did not help: I > still got 7 in a 10 minute boot. > > With the patch backported to 7.2.9, there were no timeouts in 13+ hours > of normal use (~340k reads). Average read latency went from 77 ms to > 0.49 ms. Apart from context, the only change the backport needed was > adding struct vmd_dev::features, which 7.2 doesn't have. > > Since this fixes 30 second stalls on laptops that are already shipping, > would it be suitable for stable? Yes, I think so. I added stable tags to both: 6fc5bcb43436 ("PCI: vmd: Flush DMA writes before handling MSI on Meteor Lake") 78b25e75d082 ("PCI: vmd: Flush DMA writes before handling MSI on Arrow Lake") The 8086:7d0b Arrow Lake-H ID is actually covered by the Meteor Lake patch. > Tested-by: Varsh Satti