Comment 36 for bug 1209008

Revision history for this message
Laércio de Sousa (lbssousa) wrote : Re: [Bug 1209008] Re: [SRU] X doesn't work for video cards with non-KMS drivers on non-seat0 seats

You could also disable light-locker for user logged in seat-1 and see if
problem persists.

Em qua, 17 de dez de 2014 18:44, Laércio de Sousa <email address hidden>
escreveu:

> What about your lightdm.log file? And your Xorg.1.log? Any suspect
> message?
>
> Em qua, 17 de dez de 2014 18:41, Andrzej Pietrasiewicz <
> <email address hidden>> escreveu:
>
> Regarding the doubt whether not coming back of seat-1 greeter is caused
>> by the screenscaver kicking-in: that is not the case. I checked again
>> and did a quick suspend and then resume and then looked up the
>> x-1-greeter.log and there was no line about the screensaver. It does
>> activate but far later than the failed suspend/resume.
>>
>> --
>> You received this bug notification because you are subscribed to the bug
>> report.
>> https://bugs.launchpad.net/bugs/1209008
>>
>> Title:
>> [SRU] X doesn't work for video cards with non-KMS drivers on non-seat0
>> seats
>>
>> Status in X.Org X server:
>> Fix Released
>> Status in xorg-server package in Ubuntu:
>> Fix Released
>> Status in xorg-server source package in Trusty:
>> Fix Committed
>>
>> Bug description:
>> [Impact]
>>
>> * In Xorg-server versions older than 1.16, if Xorg is started as a
>> non-seat0 X server (i.e. if it was started with "-seat XXXX" option
>> where "XXXX" != "seat0"), it only probes platform bus for graphics
>> devices, leaving devices with non-KMS drivers (like NVIDIA proprietary
>> drivers and old ones like xf86-video-siliconmotion) unreachable.
>>
>> Patch "xfree86_allow_fallback_to_pci_bus_probe_for_non_seat0.patch"
>> from lp:~ubuntu-multiseat/xorg-server/trusty-matchseat fixes this.
>>
>> * systemd-logind has no intrinsic mechanism to assign non-KMS graphics
>> devices to seats. In this case, one should tag another seat device
>> (keyboard, USB hub, etc.) in udev as "master-of-seat", and provide a
>> suitable xorg.conf for that seat. In order to avoid that a given
>> xorg.conf affects other seats, it should be passed to Xorg via
>> "-config xorg.conf.custom" option, which requires X server command
>> line customization support in DM in use (GDM, for example, has no such
>> support).
>>
>> Patch "xfree86_add_matchseat_key_to_xorg_conf.patch" from lp:~ubuntu-
>> multiseat/xorg-server/trusty-matchseat introduces a new MatchSeat key
>> for xorg.conf sections "Device", "Screen", and "ServerLayout", which
>> will target a given seat only. Example file
>> /etc/X11/xorg.conf.d/90-seat-1.conf:
>>
>> Section "Device"
>> Identifier "card0"
>> Driver "nvidia"
>> Option "NoLogo" "True"
>> # This section will only apply for seat-1
>> MatchSeat "seat-1"
>> EndSection
>>
>> * systemd-logind can't handle any VT switching for non-seat0 seats,
>> but Xorg-server older than 1.16 still opens VT even if it's started as
>> a non-seat0 X server. This may lead to a race condition between X
>> servers: if a non-seat0 one is started before a seat0 one, the former
>> "steals" VTs from the later. If a seat0 X server can't open VTs,
>> systemd-logind can't activate sessions for seat0, leaving user without
>> sound or usb input support, for example.
>>
>> Patch "xfree86_keep_non_seat0_from_touching_vts.patch" from lp
>> :~ubuntu-multiseat/xorg-server/trusty-matchseat fixes this.
>>
>> [Test Case]
>>
>> * Set up a multiseat system where your non-seat0 seats use non-KMS
>> video drivers (you may need to tag another device in udev as "master-
>> of-seat" in order to achieve it).
>>
>> * When LightDM/GDM tries to start a Xorg server for your non-seat0
>> seats, it will end up with the following error: "(EE) No devices
>> found".
>>
>> * After applying
>> xfree86_allow_fallback_to_pci_bus_probe_for_non_seat0.patch, you can
>> configure your seats in LightDM by setting appropriate "xserver-
>> config" properties for each seat. However, you can't configure them in
>> GDM.
>>
>> * After applying xfree86_add_matchseat_key_to_xorg_conf.patch,
>> configure your seats properly and restart LightDM/GDM services (or
>> reboot your computer) repeatedly. In some iterations, it may happen
>> that logind can't activate graphical sessions for seat0. If it occurs,
>> check output of command "ps -FC Xorg" and you'll see that a non-seat0
>> Xorg server has a lower PID than seat0 one. Moreover, the non-seat0
>> has opened a TTY, while the seat0 hasn't.
>>
>> [Regression Potential]
>>
>> * Very low. All these patches were well tested in xorg-server "trusty"
>> package available in ppa:ubuntu-multiseat/ppa.
>>
>> To manage notifications about this bug go to:
>> https://bugs.launchpad.net/xorg-server/+bug/1209008/+subscriptions
>>
>