no gdm3 greeter with nvidia quadro and modeset=1, discrete nvidia (not optimus)

Why does the gdm option to disable wayland not make gdm and lightdm
behaviour identical in whatever they do to the nvidia driver when
modeset=1?

On 14 September 2017 at 11:36, Daniel van Vugt <
<email address hidden>> wrote:

> ** Summary changed:
>
> - no gdm3 greeter with nvidia quadro and modeset=1, discrete nvidia (not
> optimus)
> + no gdm3 greeter with nvidia quadro and modeset=1, discrete nvidia (not
> optimus)
>
> ** Tags added: nvidia
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1714881
>
> Title:
> no gdm3 greeter with nvidia quadro and modeset=1, discrete nvidia (not
> optimus)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/gdm/+bug/1714881/+subscriptions
>

--
Tim Richardson

"reproduced on two Thinkpad laptops with bios set to Discrete graphics"

Weird, I only get this problem if the bios is set to: "Hybrid Graphics", and everything works on Discrete Graphics.

Details of how I've set those: https://askubuntu.com/questions/973605/ubuntu-17-10-boot-stuck-at-message-started-nvidia-persistence-daemon-after-ins/976578#976578

Lenovo P51, UEFI BIOS Version N1UE40W, NVIDIA Quadro M1200 Mobile, nvidia-384 installed from software-properties-gtk.

Are you using modeset=1 ?

On 15 November 2017 at 18:11, Ciro Santilli 六四事件 法轮功 <
<email address hidden>> wrote:

> "reproduced on two Thinkpad laptops with bios set to Discrete graphics"
>
> Weird, I only get this problem if the bios is set to: "Hybrid Graphics",
> and everything works on Discrete Graphics.
>
> Details of how I've set those:
> https://askubuntu.com/questions/973605/ubuntu-17-10-boot-stuck-at-
> message-started-nvidia-persistence-daemon-after-ins/976578#976578
>
> Lenovo P51, UEFI BIOS Version N1UE40W, NVIDIA Quadro M1200 Mobile,
> nvidia-384 installed from software-properties-gtk.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1714881
>
> Title:
> no gdm3 greeter with nvidia quadro and modeset=1, discrete nvidia (not
> optimus)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/gdm/+bug/1714881/+subscriptions
>

--
Tim Richardson

Ciro, you have reported "works for me" but you have not confirmed that you are actually trying to reproduce the bug. The problem occurs when using modeset=1. You do not mentioned that here or in your related answer on askubuntu

If you are not using modeset=1, which is essential for people using Optimus who want to avoid tear-free graphics, then please clarify. This bug still exists for me, on both of my ThinkPads, and also with Fedora 27.

Another user has report this on the nvidia linux board. This user reproducts the problem exactly, and reports a workaround which narrows down the problem. I haven't yet verified this workaround.
While this user has both intel and nvidia, he/she does not appear to be using a laptop.

Hey guys, I too have noticed something strange with GDM when trying to enable PRIME synchronization with modeset=1 for the nvidia_drm on Ubuntu 17.10.

I have a desktop with an Intel i7 Coffee Lake 8700K and Titan Xp and one monitor is plugged into the iGPU while the other is to the dGPU. When turning on KMS for the nvidia_drm during modprobe phase, GDM only starts on the iGPU monitor and no monitor on the dGPU is detected and a blank screen occurs.

This is fixed by kill GDM and initiating a sudo startx command from SSH which initiates a gnome-session with both monitors now detected and PRIME sync working on the iGPU monitor.

Whats' interesting is that immediately after killing the startx command, and restarting GDM, both monitors are now detected and logging in results in the iGPU monitor now showing PRIME sync in xrandr

The user I referred to in the last comment has proposed changes to
/lib/systemd/system/gdm3.service

to fix the problem.

I have added his proposed changes to this report:

https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1716857

In 18.10 (pre-release) this bug is no longer present.

Thanks. If a fix exists in any release (even pre-release) then we mark it as Fix Released.

Experiencing this trying to roll a fresh Arch Linux installation with 1060 GPU

This bug is still present in 19.04 and 19.10 (pre-release), my comment above was premature.

Nvidia release notes for Linux, Solaris, and FreeBSD driver 440.26 [beta release] [long-lived branch release] (2019-10-17) have a comment:

"Fixed a bug that could cause a blank screen on some DisplayPort monitors when logging in to GNOME, if the nvidia-drm kernel module parameter modeset=1 is specified."

I haven't tested this, I hope the beta driver gets packaged.

Status changed to 'Confirmed' because the bug affects multiple users.