Dell Customer Communication - Confidential > -----Original Message----- > From: Klaus Kusche <klaus.kus...@computerix.info> > Sent: Tuesday, October 29, 2019 3:27 PM > To: linux-desktops; linux-precision-Lists; Limonciello, Mario > Subject: Linux on Dell Precision 7740 notebook: Several BIOS-related questions > > > [EXTERNAL EMAIL] > > > Hello, > > I just installed Gentoo on a Dell Precision 7740 notebook, > using a self-configured kernel (currently 5.3.7). > > I noticed some strange things which are most likely related to Dell's BIOS or > ACPI. > > There is nothing seriously wrong at the user level, > so I don't want to open an official support case at Dell for these things. > > > 1.) The ACPI thermal zone is non-functional: > The default thermal zone (thermal zone 0) is the acpi thermal zone. > It initializes without errors, however, > it constantly reports 25 C, independent of load or real temperature. > > All other thermal zones report correct values varying with load > (except for the iwlwifi thermal zone, which is a known bug). > > > 2.) When load is slowly increased on all cores, > Intel pstate usually manages to keep temperature within limits. > But when load suddenly rises from almost nothing to 100 % busy > (especially on a single core only), > the processor exceeds 100 C and causes mce throttling > (for fractions of a second only): > Oct 29 20:27:10 lap kernel: mce: CPU4: Core temperature above threshold, cpu > clock throttled (total events = 1) > <repeated for all cores> > Oct 29 20:27:10 lap kernel: mce: CPU4: Core temperature/speed normal > <also repeated for all cores>
I would recommend that if you haven't already, you install thermald. You might also have a better experience with extracting values using dptfxtract to feed into thermald. > > > 3.) When booting, there is a single kernel message of loglevel error > which stands out in red in journalctl > and which gets displayed on all text consoles (very annoying): > > kernel: iwlwifi 0000:6f:00.0: BIOS contains WGDS but no WRDS > > What does this message mean? > Is there anything I can do about this message? > (wifi works in spite of the error) > If possible, you should probably submit a patch to iwlwifi driver to downgrade this message to debug. It really isn't useful to many people typically. > > 4.) There are some kernel warning messages in the journal while booting: > > kernel: ACPI: [Firmware Bug]: BIOS _OSI(Linux) query ignored > Harmless. > kernel: acpi PNP0C14:02: duplicate WMI GUID 05901221-D566-11D1-B2F0- > 00A0C9062910 (first instance was on PNP0C14:01) > kernel: wmi_bus wmi_bus-PNP0C14:03: WQBC data block query control method > not found > kernel: acpi PNP0C14:03: duplicate WMI GUID 05901221-D566-11D1-B2F0- > 00A0C9062910 (first instance was on PNP0C14:01) > kernel: acpi PNP0C14:04: duplicate WMI GUID 05901221-D566-11D1-B2F0- > 00A0C9062910 (first instance was on PNP0C14:01) > kernel: acpi PNP0C14:05: duplicate WMI GUID 05901221-D566-11D1-B2F0- > 00A0C9062910 (first instance was on PNP0C14:01) The WMI driver doesn't know how to enumerate all the extra instances. I don't think this should affect anything. > > kernel: i801_smbus 0000:00:1f.4: Accelerometer lis3lv02d is present on SMBus > but > its address is unknown, skipping registration Dell doesn't support this accelerometer, but some reverse engineered implementations exist. > > kernel: dell_wmi_aio: No known WMI GUID found You don't need this driver for your system. > > > My questions are: > > * Have I configured anything wrong when building my kernel > (e.g. missing drivers or dell-specific configs)? > > * Is there anything which should be fixed in the linux kernel > or in Dell's BIOS and ACPI implementation, > i.e. do any of these things point to a real bug? > > * Can all these things be safely ignored, > or is there anything I should worry about? > > * Are these problems / messages well known, > or is it just me who gets them? > > * Whom should I contact? > > Many thanks in advance for any help! > > -- > Prof. Dr. Klaus Kusche > Private address: Rosenberg 41, 07546 Gera, Germany > +49 365 20413058 klaus.kus...@computerix.info https://www.computerix.info > Office address: DHGE Gera, Weg der Freundschaft 4, 07546 Gera, Germany > +49 365 4341 306 klaus.kus...@dhge.de https://www.dhge.de _______________________________________________ Linux-Desktops mailing list Linux-Desktops@dell.com https://lists.us.dell.com/mailman/listinfo/linux-desktops Please read the FAQ at http://lists.us.dell.com/faq
