From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy1-f172.google.com (mail-dy1-f172.google.com [74.125.82.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A47C71FECBA for ; Thu, 7 May 2026 02:52:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778122321; cv=none; b=BHuw32SQVHcRdtzZDZoxkUUiZUlFtYu4do2pV0fT43kZ6WiJ6zRzGfF+V8oXB/S2yeu63cpf9bH0O7nPnYFnf7I6PGjM2sOkeXWv3XsNzK0yPxisSJiSk+gk/ZwIPAnn56mbMelcBbAnKx18lpOTha05DrWLUZJxwNr3HFiRUww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778122321; c=relaxed/simple; bh=ZzunOxEtRWovf22x4NSwe82YRiPXQweJT42C5WwKKfE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=HcANwN7hcJ2yxRRONAxOOMtcvZxjY+ZLvwpzi89xCESQeh3LMPZOe7wTs08Q4IgLPqHMtiBXiS/AsX4w83+d5s1IBcu5hrhD2pKXkqiL++D++lBVU7Rk+A9m8IfC5tGXU8vI6toM1BGXN9WPOqOBTbc3x9PP3PExD9U+plJCtgk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=hGieXcro; arc=none smtp.client-ip=74.125.82.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hGieXcro" Received: by mail-dy1-f172.google.com with SMTP id 5a478bee46e88-2c156c4a9efso480826eec.1 for ; Wed, 06 May 2026 19:52:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1778122320; x=1778727120; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=S/TiqWPCIVOUr4GYVcJCLO+QpFwEOSUT7p9be3OEgbI=; b=hGieXcroqCYtUkUrqY9dwcEmnARipXp5TO1l6m2gezMiE6yitUmLGDzjsmmefclfJ3 mX2py3CSt3Ulu6+pq+BrZ9hqIHNrPQbo6gv17deBOf8NQp4CeLz3ZKmKUx8Yu2Lmie+U KIGbiVatjrNMjapGEq+gi1uU4/8GQGIXiMlj/ksqlwjk0JfdQbSXEPucEXtyO5rHPmxi TTUxc0kjEMK4cVQoenkMI8ELarOe7c8j3BSBEzUZCpu2sMaq27gUgSup3w2FqtMXkhwx /shP/KWuRrx9M8tmHqrvltJNH9WGHmBNUNxWTjQRoz8bdiesqK4VOzQ9Adoui2xU24xa jq4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778122320; x=1778727120; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=S/TiqWPCIVOUr4GYVcJCLO+QpFwEOSUT7p9be3OEgbI=; b=IKiqIvn/VtWoG+Fw3hw0f6bXNqVoD2o3YP/EzbdOlsoyA4rJWMeJkE5KJfBwMH1ITN 8m2DNrI20If0Zn/AEGSsE3/o8tzPuNO5gbbBAhq550/1/m6WO9wSFRj0kDebZTJF8iDl 8KcZz7k1w5S5YTooM8hS8jxhSo0GiW1+xQlJLOQ8CXH9Fn2xEl1Fh1+wy/A8T0fUzlGK Qu7aJlpUcWX/PrkzFCso8UOWemOW3sVgGG2ZHXuL66NjgMcFhYEM8MXsW93xQRhAIzFI 2TmKJXVX+zhQ4rzzySK03QW0sXjd4PQdolo828Nx0FIS1eQFpVxpldHdqoDPksNh4Gh9 U/Rg== X-Forwarded-Encrypted: i=1; AFNElJ/YuyhXD3D0BOaN/gWt28/ooxaNAl/nLQLG96tX49sh8+Vz7hW/nX7FOWg2Frc5MLNgsg5+JavaF8Y=@vger.kernel.org X-Gm-Message-State: AOJu0YzLCUKUAdHi8FVRPoT8t//Z7E3XcWX701E89evx92Pcj2lUKzzJ BQhxOEPy0q/lPt1VeuiYjFCThboBnohULZmyha2DRvpOrhbvXEPD8+8I X-Gm-Gg: AeBDiesreKAqXKafnJXBq5oohwry+zhCgzMpczoVf0reTYosfOi3WprGP9nbj+3dNDF Vn2LYYvL6GdlX6jbjEhRKrdr6CojTM1B5MzNiDL4r5p/OHUd0+8sJ6teK+SX8FayGQCBGjnAeps LqU5x2SZ746gnQ8d0FGlbiueq7W4j93g8ym/rhwGtClBdsyCmo1tBJeUeROAVLlYP2WMwa9e3a3 IpP0qXoMTBCwRH0lS9iDQXQ45uGnk5b+9hplD02bxTgoGLRom5t5I8HK5Opld14ZtnyLI9nOTK5 zPRhSVjRsbFtnDkVR98wuY9yWrI+wuX0RcqF+MqIn85jTtou7foswSzBganyX88aro6yGXaac5O jszgShyateMZJ7LgzJIX6qywYW8i4GQTTRuIH20XfYpKrGQ3MfmTG9XXwG5vprfg6K6YkGOYGZq CXO9V5rhvFuWBwlackdBQ+w85Y4l0P30EgRGPS+1R/M3G4dZ+2jys= X-Received: by 2002:a05:7300:2322:b0:2ef:2878:7ad0 with SMTP id 5a478bee46e88-2f55094d023mr2547311eec.27.1778122319696; Wed, 06 May 2026 19:51:59 -0700 (PDT) Received: from [192.168.86.23] ([136.25.189.61]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-2f56cec763fsm6263436eec.4.2026.05.06.19.51.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 06 May 2026 19:51:59 -0700 (PDT) Message-ID: <26361f34-f24a-4289-bfc6-799b8f189fc1@gmail.com> Date: Wed, 6 May 2026 19:51:57 -0700 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] PCI/ASPM: Don't reconfigure ASPM entering low-power state To: Bjorn Helgaas , "Carlos Bilbao (Lambda)" Cc: bhelgaas@google.com, eduardo.habkost@lambdal.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, bilbao@vt.edu References: <20260506181012.GA803978@bhelgaas> Content-Language: en-US From: Carlos Bilbao In-Reply-To: <20260506181012.GA803978@bhelgaas> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hey Bjorn. On 5/6/26 11:10, Bjorn Helgaas wrote: > On Mon, Apr 27, 2026 at 09:01:04PM -0700, Carlos Bilbao (Lambda) wrote: >> From: Carlos Bilbao >> >> Reconfiguring ASPM when a device transitions to low-power state can enable >> L1.1/L1.2 substates on the PCIe link at a time when the device is sleeping >> and may be unable to exit them. ASPM should be reconfigured on D0 entry >> (resume), not on the way down. >> >> pci_set_low_power_state() calls pcie_aspm_pm_state_change() after writing >> D3hot to PCI_PM_CTRL. pcie_aspm_pm_state_change() resets link->aspm_capable >> to link->aspm_support and then calls pcie_config_aspm_path(), which can >> enable ASPM L1.1/L1.2 substates on the PCIe link. If the device cannot >> recover the link from L1.2 while in D3hot, subsequent config space reads >> return 0xFFFF ("device inaccessible") and pci_power_up() fails with message >> "Unable to change power state from D3hot to D0, device inaccessible". > Carlos, do you have a few lines of dmesg showing this issue that we > could quote to help people match the issue with this fix? Thank you for reviewing this. Only the error message: [160459.607156] vfio-pci 0000:5d:00.0: Unable to change power state from D3cold to D0, device inaccessible Thanks, Carlos