Public bug reported:
Ubuntu 24.04.5 LTS has a long graphical startup delay on a Lenovo
ThinkPad P16 Gen 3 with Intel integrated graphics and an NVIDIA RTX PRO
3000 Blackwell Laptop GPU.
System:
- Ubuntu 24.04.5 LTS
- Lenovo ThinkPad P16 Gen 3
- Kernel: 6.17.0-1032-oem
- NVIDIA driver: 595.91.07 open kernel module
- prime-select: on-demand
- nvidia-prime: 0.8.17.2
- ubuntu-drivers-common: 1:0.9.7.6ubuntu3.7
- gdm3: 46.2-1ubuntu1~24.04.9
- Secure Boot disabled
- No /etc/X11/xorg.conf
- /etc/X11/xorg.conf.d is empty
Boot timing:
systemd-analyze:
Startup finished in 17.436s (firmware) + 2.250s (loader) +
2.281s (kernel) + 40.321s (userspace) = 1min 2.289s
systemd-analyze blame includes:
36.917s plymouth-quit-wait.service
8.358s gpu-manager.service
The graphical login initialization spends a significant amount of time
probing the Intel and NVIDIA displays.
xrandr --listproviders gives:
Providers: number : 2
Provider 0: id: 0x47 cap: 0x9, Source Output, Sink Offload
crtcs: 4 outputs: 5 associated providers: 1 name:modesetting
Provider 1: id: 0x258 cap: 0x2, Sink Output
crtcs: 4 outputs: 5 associated providers: 1 name:NVIDIA-G0
During GDM startup the following error occurs:
X Error of failed request: BadValue
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 35 (RRSetProviderOutputSource)
Value in failed request: 0x47
There also appears to be a possible problem in /usr/sbin/prime-offload.
The installed script determines the providers using:
src=$(echo "$output" | grep " Source" | head -n1 ...)
sink=$(echo -e "$output" | grep " Sink" | head -n1 ...)
On this system the modesetting provider contains both:
Source Output, Sink Offload
Therefore grep " Sink" appears to select the modesetting provider because
of "Sink Offload", even though the provider with the "Sink Output"
capability is NVIDIA-G0.
This appears to cause prime-offload to attempt to use the modesetting
provider incorrectly and corresponds with the RRSetProviderOutputSource
BadValue error above.
After startup the system works normally and both providers are present.
Expected behavior:
GDM/PRIME should identify NVIDIA-G0 as the Sink Output provider and start
without the extended graphics initialization delay.
Actual behavior:
prime-offload appears to select an incorrect provider, RANDR reports
BadValue, and graphical startup takes considerably longer.
I have deliberately not modified /usr/sbin/prime-offload or the NVIDIA
configuration because I want to keep the packaged system configuration
unchanged.
ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: nvidia-prime 0.8.17.2
ProcVersionSignature: Ubuntu 6.17.0-1032.32-oem 6.17.13
Uname: Linux 6.17.0-1032-oem x86_64
ApportVersion: 2.28.3-0ubuntu0.1
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Thu Sep 17 13:08:21 2026
Dependencies:
InstallationDate: Installed on 2026-02-26 (203 days ago)
InstallationMedia: Ubuntu 24.04.4 LTS "Noble Numbat" - Release amd64 (20260210)
PackageArchitecture: all
ProcEnviron:
LANG=en_US.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
SourcePackage: nvidia-prime
UpgradeStatus: No upgrade log present (probably fresh install)
** Affects: nvidia-prime (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug noble
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https://bugs.launchpad.net/bugs/2167575
Title:
Slow GDM startup on Intel/NVIDIA hybrid system: prime-offload selects
modesetting as both source and sink
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https://bugs.launchpad.net/ubuntu/+source/nvidia-prime/+bug/2167575/+subscriptions
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