From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roland Singer Subject: Re: Kernel Freeze with American Megatrends BIOS Date: Wed, 31 Aug 2016 13:12:30 +0200 Message-ID: <98b2ae5b-399b-8337-18dc-98ac2480746f@desertbit.com> References: <20160829235403.GA14177@localhost> <1d1bfdc2-f23d-9816-e4e3-ae676105dc39@desertbit.com> <20160830130634.GA16426@localhost> <735da66c-aaf3-8c27-2d59-f62e8c85d3aa@desertbit.com> <43ce7a5b-8331-fec2-f598-afcb13ba3785@desertbit.com> <1c761bab-f82b-3f43-c4f0-c7a8eff94f25@desertbit.com> <20160830192112.GA18045@al> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20160830192112.GA18045@al> Sender: linux-pci-owner@vger.kernel.org To: Peter Wu , Ilia Mirkin Cc: Emil Velikov , Bjorn Helgaas , Linux PCI , "Linux-Kernel@Vger. Kernel. Org" , ML dri-devel , "linux-acpi@vger.kernel.org" List-Id: linux-acpi@vger.kernel.org Am 30.08.2016 um 21:21 schrieb Peter Wu: > On Tue, Aug 30, 2016 at 02:13:46PM -0400, Ilia Mirkin wrote: >> On Tue, Aug 30, 2016 at 2:02 PM, Roland Singer >> wrote: >>> I configured bbswitch to not set any states automatically... >>> So it's possible to obtain and verify the GPU power state. >>> >>> However I removed the bbswitch module and booted with nouveau. >>> >>> Kernel 4.7.2: nouveau switches the discrete GPU off. >>> I can't trigger the freeze, because bbswitch is missing. >>> I'll work with the system and see if it will freeze. >>> >>> Kernel 4.8-rc4: nouveau does not care about the power state and >>> the discrete GPU is never switched off. I will notice >>> this, because the second cooling FAN will stop... >>> Same log messages as send before. >> >> That's surprising. I believe there's an issue with the new logic when >> there's an HDMI audio subdevice. However that only appears if there's >> a cable plugged in, at least in the systems Peter tested. You should >> be able to see whether it's there or not with 'lspci'. > > I doubt that the audio device is responsible here, that should only show > up after following very specific steps (runtime suspend/resume (PCI or > ACPI magic), remove PCI device, rescan bus). > >> You can check for sure by looking in the vgaswitcheroo state. It >> should say DynOff when it's powered off. >> >> Either way, I think using bbswitch + nouveau isn't supported by >> anyone, so if you want to use it that way, you're on your own. (You >> may want to load nouveau with runpm=0 so that nouveau doesn't try to >> manage the GPU suspend stuff.) > > I understood that Roland's intent is to check the power state, not use > the suspend functionality of bbswitch, if you load bbswitch without > module options amd do not write to /proc/bbswitch, then it allows you to > read out the actual status (you could also just use lspci -H1 for that > though). > lspci -H1 works perfect. Thanks. Just tried to verify the output with lspci -H1. I unloaded the nouveau module and modprobe freezed with: $ modprobe -r nouveau nouveau 0000:01:00.0: pci: failed to adjust lnkctl speed nouveau 0000:01:00.0: fb: init failed. -22 nouveau 0000:01:00.0: init failed with -22 nouveau: DRM:00000000:00000000: init failed with -22 nouveau: DRM:00000000:00000000: init failed with -22