Re: [REGRESSION] Xorg segfaults on Asus Chromebook CP101 with Linux v5.2 (was Asus C101P Chromeboot fails to boot with Linux 5.2)

From: Ezequiel Garcia
Date: Sat Jul 13 2019 - 18:59:08 EST


On Sat, 13 Jul 2019 at 13:43, Alex Dewar <alex.dewar@xxxxxxxxx> wrote:
>
> On 13/07/2019 16:17, Heiko Stuebner wrote:
> > Hi,
> >
> > Am Samstag, 13. Juli 2019, 13:38:45 CEST schrieb Alex Dewar:
> >> I initially thought my machine was failing to boot entirely, but it
> >> turns out it was just failing to start the display manager. I managed to
> >> escape to a tty by hammering the keyboard a bit.
> >>
> >> I suspect the culprit is the rockchip_vpu driver (in staging/media),
> >> which has been renamed to hantro in this merge window. When I run startx
> >> from a terminal, X fails to start and Xorg segfaults (log here:
> >> http://users.sussex.ac.uk/~ad374/xorg.log). X seems to work without any
> >> issues in v5.1.
> >
> > 5.2 also has support for Panfrost (Mali-Midgard GPUs) but I'm not
> > sure if it already can support X11 yet and your X11 log mentions
> > libglamoregl in the segfault stack trace.
> >
> > Apart from it bisect that Greg suggested you could also just try
> > blacklisting either panfrost or vpu kernel modules
> > /etc/udev/somewhere . This would prevent them from loading
> >
> > Hope that helps
> > Heiko
> >
> >
>
> Hi Heiko,
>
> Thanks for this. I blacklisted the panfrost driver and X magically
> started working again.
>
> I'll try to do a bisect later to find the offending commit though.
>
> In related news, it also seems that the sound and wifi drivers aren't
> working either in 5.2 (although I need to do a bit more testing to
> confirm the latter).
>

Adding myself and Tomeu.

Perhaps we need to disable Panfrost from defconfig from now?

Regards,
Eze