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 9D4BA762EB; Wed, 11 Sep 2024 19:05:19 +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=1726081519; cv=none; b=RQ0T98d7B62qt21IQSS4bK4gBevgKhwFBAfppVWS8mn5EHIZ6iglVyzRFU3/klqfcmc14XcEPY7Y1OQS4EHoc0Ju7UKyTOTsQcI1VfkC6iwtUwqsQPzo3J1XV0ay/5wS/dBlJdJlomx9X/x0/aHPLNMSJUJqNnSxAoDNCobl3Xs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726081519; c=relaxed/simple; bh=0D6HKZtwwVTLn2g82F7IMTiNI9WZKYvVIf++vYQyoVA=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=rfdU7ascJc3c3qeR3aBm/a3ebKBKy4CnMqx5i91CAvP9LniY0SFJjegDwj50C2aTT6L3JCOFuhT1A/v+vPh2ENCRZDxDTqGIYVSHMVSZcItWpvRLRMW0UplrgG8zCjiGT/R1oKTnihpJuAdes/5oRi6WyC3ey06Wim3fhOCE0Fc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C9lDfpTn; 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="C9lDfpTn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE11CC4CEC0; Wed, 11 Sep 2024 19:05:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726081519; bh=0D6HKZtwwVTLn2g82F7IMTiNI9WZKYvVIf++vYQyoVA=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=C9lDfpTn6FaD8EY3GnDtWdqF8qz5r5Y0ZkLfeM3C+5v1qNaMiVekK+llbVTW5pXQH NCqI5NOK6WpXnXyfyznbsIZ2bHxvpznh8mc2wGd0mMNHhAISGzPDJQB4wMbm9F1zJZ ORIC2zgNocbXuz0Dy3P0vzcUL+DuXvrAkrS7cMv6i7M6cly6rKoDiwOfJAOxNmPGQl PuGlR4lEhaqiymPFhpm8VYlxjNBstWt3npxeShaf/32cxUafNE3Xxk0cEUuE7eRvn9 LIeUNGjtVaIZ1kzyhb8K0EylMHlDgZ9Ii8RiBf87+1yxCSa/kTz+Iozc2NIsUvit0/ /c0V2Twcm/veA== Date: Wed, 11 Sep 2024 14:05:16 -0500 From: Bjorn Helgaas To: Kai-Heng Feng Cc: bhelgaas@google.com, mario.limonciello@amd.com, mika.westerberg@linux.intel.com, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI/PM: Put devices to low power state on shutdown Message-ID: <20240911190516.GA644336@bhelgaas> Precedence: bulk X-Mailing-List: linux-pm@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: <20240712062411.35732-1-kai.heng.feng@canonical.com> On Fri, Jul 12, 2024 at 02:24:11PM +0800, Kai-Heng Feng wrote: > Some laptops wake up after poweroff when HP Thunderbolt Dock G4 is > connected. > > The following error message can be found during shutdown: > pcieport 0000:00:1d.0: AER: Correctable error message received from 0000:09:04.0 > pcieport 0000:09:04.0: PCIe Bus Error: severity=Correctable, type=Data Link Layer, (Receiver ID) > pcieport 0000:09:04.0: device [8086:0b26] error status/mask=00000080/00002000 > pcieport 0000:09:04.0: [ 7] BadDLLP > > Calling aer_remove() during shutdown can quiesce the error message, > however the spurious wakeup still happens. > > The issue won't happen if the device is in D3 before system shutdown, so > putting device to low power state before shutdown to solve the issue. > > I don't have a sniffer so this is purely guesswork, however I believe > putting device to low power state it's the right thing to do. My objection here is that we don't have an explanation of why this should matter or a pointer to any spec language about this situation, so it feels a little bit random. I suppose the problem wouldn't happen if AER interrupts were disabled? We already do disable them in aer_suspend(), but maybe that's not used in the shutdown path? My understanding is that .shutdown() should turn off device interrupts and stop DMA. So maybe we need an aer_shutdown() that disables interrupts? > Link: https://bugzilla.kernel.org/show_bug.cgi?id=219036 > Signed-off-by: Kai-Heng Feng > --- > drivers/pci/pci-driver.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c > index af2996d0d17f..4c6f66f3eb54 100644 > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -510,6 +510,14 @@ static void pci_device_shutdown(struct device *dev) > if (drv && drv->shutdown) > drv->shutdown(pci_dev); > > + /* > + * If driver already changed device's power state, it can mean the > + * wakeup setting is in place, or a workaround is used. Hence keep it > + * as is. > + */ > + if (!kexec_in_progress && pci_dev->current_state == PCI_D0) > + pci_prepare_to_sleep(pci_dev); > + > /* > * If this is a kexec reboot, turn off Bus Master bit on the > * device to tell it to not continue to do DMA. Don't touch > -- > 2.43.0 >