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 ABD8B1C5D72; Thu, 7 Aug 2025 15:52:46 +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=1754581966; cv=none; b=Tkt+UjtomVyfebJM79Prsm+qa615IR8lml3nHrPrDjF3S0/NYsg+C5bUhzWhHMUClp7Ls+EjE5KGdX78frU33Zq0NAt5kHAE/KmUsPsH/h+wpNd+TTr6YfQg7gwCLtT7ALac9eLl0966OG/dtLQmaBxdHOX87Bs2qJBKAamu52c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754581966; c=relaxed/simple; bh=YRS94p/FbNM9/y4FbArYf7EcAJfwjlAscxKZ9U1T7JE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WWlGXMn40/RPQjsEA8vUn3n5SvIR+kcxS9ZK7mKDYndBRIHIgh+87vJqiwVNZraVv45fxgkbYgGG/tKgm7MJZFs1Ta0akoUj2NPNAz42JFH8xHSc2NsYHLufHKidThOJTLn019smdV/7TOoiGMcLRpkZcbVesx2HDlaoy1pffqI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I0zNu88/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I0zNu88/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EECDBC4CEEB; Thu, 7 Aug 2025 15:52:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1754581966; bh=YRS94p/FbNM9/y4FbArYf7EcAJfwjlAscxKZ9U1T7JE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=I0zNu88/pI1njpXl57TwTnMUoFUiRSmn6pOk1qOKUF8x9lEfd97ZjHjsWSQTfW9Bh TO/UgCX3A6NBkxfJbhTA73oqf485HTiGCyAY18slvwqJHJGiHYjLHrw7zJzh8C50k4 NizCfgVGOwX7RCgcN8Tq+pyLuPP3QWgePlVSaCr4= Date: Thu, 7 Aug 2025 16:52:41 +0100 From: Greg KH To: cat Cc: regressions@lists.linux.dev, stable@vger.kernel.org Subject: Re: [REGRESSION] vfio gpu passthrough stopped working Message-ID: <2025080724-sage-subplot-3d0f@gregkh> References: <718C209F-22BD-4AF3-9B6F-E87E98B5239E@plan9.rocks> Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <718C209F-22BD-4AF3-9B6F-E87E98B5239E@plan9.rocks> On Thu, Aug 07, 2025 at 03:31:17PM +0000, cat wrote: > #regzbot introduced: v6.12.34..v6.12.35 > > After upgrade to kernel 6.12.35, vfio passthrough for my GPU has stopped working within a windows VM, it sees device in device manager but reports that it did not start correctly. I compared lspci logs in the vm before and after upgrade to 6.12.35, and here are the changes I noticed: > > - the reported link speed for the passthrough GPU has changed from 2.5 to 16GT/s > - the passthrough GPU has lost it's 'BusMaster' and MSI enable flags > - latency measurement feature appeared > > These entries also began appearing within the vm in dmesg when host kernel is 6.12.35 or above: > > [ 1.963177] nouveau 0000:01:00.0: sec2(gsp): mbox 1c503000 00000001 > [ 1.963296] nouveau 0000:01:00.0: sec2(gsp):booter-load: boot failed: -5 > ... > [ 1.964580] nouveau 0000:01:00.0: gsp: init failed, -5 > [ 1.964641] nouveau 0000:01:00.0: init failed with -5 > [ 1.964681] nouveau: drm:00000000:00000080: init failed with -5 > [ 1.964721] nouveau 0000:01:00.0: drm: Device allocation failed: -5 > [ 1.966318] nouveau 0000:01:00.0: probe with driver nouveau failed with error -5 > > > 6.12.34 worked fine, and latest 6.12 LTS does not work either. I am using intel CPU and nvidia GPU (for passthrough, and as my GPU on linux system). Can you use git bisect to find the offending commit?