X server freezed

As I was playing with bzflag, the Xserver freezed. Keyboard and mouse didn't work anymore, only ALT-SYS-R S I U B to boot.
It's the first time I've got this bug.

Mar 8 11:22:40 Ordinateur-David kernel: [ 3809.838604] nouveau 0000:05:00.0: bzflag[11340]: Unknown handle 0x000000cb
Mar 8 11:22:40 Ordinateur-David kernel: [ 3809.838608] nouveau 0000:05:00.0: bzflag[11340]: validate_init
Mar 8 11:22:40 Ordinateur-David kernel: [ 3809.838609] nouveau 0000:05:00.0: bzflag[11340]: validate: -2

$ lsb_release -rd
Description: Linux Mint 19.3 Tricia
Release: 19.3

$ apt-cache policy xserver-xorg-video-nouveau
xserver-xorg-video-nouveau:
  Installé : 1:1.0.15-2
  Candidat : 1:1.0.15-2
 Table de version :
 *** 1:1.0.15-2 500
        500 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages
        100 /var/lib/dpkg/status
---
ProblemType: Bug
.tmp.unity_support_test.0:

ApportVersion: 2.20.9-0ubuntu7.14
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: MATE
DistUpgraded: Fresh install
DistroCodename: tricia
DistroRelease: Linux Mint 19.3
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 NVIDIA Corporation GK107GL [Quadro K2000] [10de:0ffe] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company GK107GL [Quadro K2000] [103c:094c]
LightdmDisplayLog: -2
MachineType: Hewlett-Packard HP Z420 Workstation
Package: xserver-xorg-video-nouveau 1:1.0.15-2 [origin: Ubuntu]
PackageArchitecture: amd64
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.3.0-51-generic root=UUID=16ff2b10-8f36-42a7-93bd-4c84973fe52a ro quiet splash vt.handoff=1
ProcVersionSignature: Ubuntu 5.3.0-51.44~18.04.2-generic 5.3.18
Tags: tricia third-party-packages ubuntu
Uname: Linux 5.3.0-51-generic x86_64
UnreportableReason: Ce paquet n'est pas officiellement pris en charge par Linux. Veuillez désinstaller tout paquet tiers et réessayer.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip docker kvm lpadmin lxd plugdev sambashare sudo vboxusers
_MarkForUpload: True
dmi.bios.date: 10/29/2019
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: J61 v03.96
dmi.board.asset.tag: VANTYGHEM
dmi.board.name: 1589
dmi.board.vendor: Hewlett-Packard
dmi.board.version: 0.00
dmi.chassis.asset.tag: VANTYGHEM
dmi.chassis.type: 6
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvrJ61v03.96:bd10/29/2019:svnHewlett-Packard:pnHPZ420Workstation:pvr:rvnHewlett-Packard:rn1589:rvr0.00:cvnHewlett-Packard:ct6:cvr:
dmi.product.family: 103C_53335X G=D
dmi.product.name: HP Z420 Workstation
dmi.product.sku: WM445ET#ABF
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.13.1+18.04.20180302-0ubuntu1
version.libdrm2: libdrm2 2.4.99-1ubuntu1~18.04.2
version.libgl1-mesa-dri: libgl1-mesa-dri 19.2.8-0ubuntu0~18.04.3
version.libgl1-mesa-glx: libgl1-mesa-glx 19.2.8-0ubuntu0~18.04.3
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4.4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.5-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2