On 2017-03-22 10:25 +0000, Oliver Elphick wrote:
> I am unable to start X using a Matrox Millennium G550 PCIe card.
>
> This is what I think is the relevant part of the log for the session:
>
> #011compiled for 1.19.2, module version = 0.1.0
> #011ABI class: X.Org Video Driver, version 23.0
> (--) MGA(0): Chipset: "mgag550"
> xf86TokenToOptinfo: table is NULL
> xf86TokenToOptinfo: table is NULL
> (==) MGA(0): Using HW cursor
> (--) MGA(0): Linear framebuffer at 0xF0000000
> (--) MGA(0): MMIO registers at 0xF7020000
> (--) MGA(0): Pseudo-DMA transfer window at 0xF6800000
> (EE) MGA(0): Unable to map Framebuffer F0000000 2000000. Permission
> denied (13)
> (II) MGA(0): Creating default Display subsection in Screen section
> #011"Default Screen Section" for depth/fbbpp 24/32
> (==) MGA(0): Depth 24, (--) framebuffer bpp 32
> (==) MGA(0): RGB weight 888
> (==) MGA(0): Using AGP 1x mode
> (==) MGA(0): Using XAA acceleration
> (WW) MGA(0): Could not retrieve video BIOS!
> (EE) MGA(0): Unable to detect video RAM.
> (II) UnloadModule: "mga"
>
> The full log is attached.
>
> Can anyone indicate what the problem is, please?
Probably that the X server is no longer running with root rights, and
it has to do that if there is no kernel driver for the graphics card.
See /usr/share/doc/xserver-xorg-core/NEWS.Debian.gz:
,----
| xorg-server (2:1.17.3-1) unstable; urgency=medium
|
| The Xorg server is no longer setuid root by default. This change reduces
the
| risk of privilege escalation due to X server bugs, but has some side
effects:
|
| * it relies on logind and libpam-systemd
| * it relies on a kernel video driver (so the userspace component doesn't
| touch the hardware directly)
| * it needs X to run on the virtual console (VT) it was started from
| * it changes the location for storing the Xorg log from /var/log/ to
| ~/.local/share/xorg/
|
| On systems where those are not available, the new xserver-xorg-legacy
package
| is needed to allow X to run with elevated privileges. See the
| Xwrapper.config(5) manual page for configuration details.
|
| -- Julien Cristau <jcris...@debian.org> Tue, 27 Oct 2015 22:54:11 +0000
`----
In short, you need to install xserver-xorg-legacy.
Cheers,
Sven
