Re: [gentoo-user] Can't get X running in Kernel 4.4.26. [Solved]

[Mick]

On Sunday 05 Feb 2017 13:08:18 Alan Mackenzie wrote:
> On Thu, Dec 29, 2016 at 14:52:08 +0000, J. Roeleveld wrote:
> > On December 29, 2016 3:24:27 PM GMT+01:00, Alan Mackenzie <acm@×××.de>
wrote:
> > >Hi, Gentoo.
> > >
> > >I'm having trouble with my kernel 4.4.26.  It will do everything
> > >expected of it except for running X Windows.
> > >
> > >I've checked I've got the kernel configuration set up as described in
> > >the gentoo wiki documents, unless I've overlooked something.
> > >
> > >What happens is that I run "startx", and a little while later, the X
> > >server reports that no screens are found.
> > >
> > >More precisely, the following appears in Xorg.0.log:
> > >        KAVERI, KAVERI, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII,
> > >        HAWAII, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII
> > >
> > >[    47.952] (II) modesetting: Driver for Modesetting Kernel Drivers:
> > >kms
> > >[    47.952] (--) using VT number 7
> > >
> > >[    47.963] (II) [KMS] Kernel modesetting enabled.
> > >[    47.963] (WW) Falling back to old probe method for modesetting
> > >[    47.963] (EE) No devices detected.
> > >[    47.963] (EE)
> > >Fatal server error:
> > >[    47.963] (EE) no screens found(EE)
> > >[    47.963] (EE)
> > >Please consult the The X.Org Foundation support
> > >
> > >         at http://wiki.x.org
> > >
> > > for help.
> > >
> > >[    47.963] (EE) Please also check the log file at
> > >"/var/log/Xorg.0.log" for additional information.
> > >[    47.963] (EE)
> > >
> > >Note the "No devices detected".
> > >
> > >
> > >The corresponding piece of the working Xorg.0.log in my older kernel
> > >
> > >is:
> > >        KAVERI, KAVERI, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII,
> > >        HAWAII, HAWAII, HAWAII, HAWAII, HAWAII, HAWAII
> > >
> > >[   188.705] (II) modesetting: Driver for Modesetting Kernel Drivers:
> > >kms
> > >[   188.705] (--) using VT number 7
> > >
> > >[   188.713] (II) [KMS] Kernel modesetting enabled.
> > >[   188.713] (WW) Falling back to old probe method for modesetting
> > >[   188.713] (WW) VGA arbiter: cannot open kernel arbiter, no
> > >multi-card support
> > >[   188.713] (II) RADEON(0): Creating default Display subsection in
> > >Screen section
> > >
> > >        "Default Screen Section" for depth/fbbpp 24/32
> > >
> > >[   188.713] (==) RADEON(0): Depth 24, (--) framebuffer bpp 32
> > >[   188.713] (II) RADEON(0): Pixel depth = 24 bits stored in 4 bytes
> > >(32 bpp pixmaps)
> > >[   188.713] (==) RADEON(0): Default visual is TrueColor
> > >[   188.713] (==) RADEON(0): RGB weight 888
> > >[   188.713] (II) RADEON(0): Using 8 bits per RGB (8 bit DAC)
> > >[   188.713] (--) RADEON(0): Chipset: "ATI Radeon HD 4550" (ChipID =
> > >0x9540)
> > >
> > >
> > >Needless to say, the kernel version is the sole difference between the
> > >non-working 4.4.26 and the working 4.0.5.
> > >
> > >Would somebody please help me track down this problem.  Thanks!
> >
> > I ended up skipping 4.4 kernels as I had problems as well.
> > Not with X, but hibernate wasn't working.
> > 4.6 and 4.8 kernels do seem to work better.
> >
> > You could try a more recent one as well.
>
> I found the problem whilst debugging the same symptoms in kernel 4.9.6.
> I'd disabled "Enable PCI quirk workarounds" in General Setup.  After
> reenabling it, my X functions again.  Don't ask me what brought me to
> suspect this setting.
>
> I mean, my PC is "relatively recent" (2009).  PCI, even PCIe, is as old
> as the hills.  Surely they got the quirks out of the chipsets by 2009?
> Apparently not!
>
> > --
> > Joost

Thanks for letting us know.  I would have *never* thought of this setting 
causing a problem with X ...  O_O

-- 
Regards,
Mick