QEMU / KVM How to change default resolution on GUEST

English Virtualization
1 

HOST:
Operating System: openSUSE Tumbleweed 20220210
KDE Plasma Version: 5.24.0
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.2
Kernel Version: 5.16.5-1-default (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-8559U CPU @ 2.70GHz
Memory: 7.6 GiB of RAM
Graphics Processor: Mesa Intel® Iris® Plus Graphics 655


raija@localhost:~> inxi -F
System:    Host: localhost Kernel: 5.16.5-1-default x86_64 bits: 64 Desktop: KDE Plasma 5.24.0
           Distro: openSUSE Tumbleweed 20220210
Machine:   Type: Mini-pc System: Intel Client Systems product: NUC8i7BEH v: J72992-306 serial: <superuser required>
           Mobo: Intel model: NUC8BEB v: J72688-306 serial: <superuser required> UEFI: Intel
           v: BECFL357.86A.0073.2019.0618.1409 date: 06/18/2019
CPU:       Info: Quad Core model: Intel Core i7-8559U bits: 64 type: MT MCP cache: L2: 8 MiB
           Speed: 600 MHz min/max: 400/4500 MHz Core speeds (MHz): 1: 600 2: 600 3: 600 4: 600 5: 600 6: 600 7: 600 8: 600
Graphics:  Device-1: Intel CoffeeLake-U GT3e [Iris Plus Graphics 655] driver: i915 v: kernel
           Display: x11 server: X.Org 1.21.1.3 driver: loaded: modesetting unloaded: fbdev,vesa resolution: 1920x1080~60Hz
           OpenGL: renderer: Mesa Intel Iris Plus Graphics 655 (CFL GT3) v: 4.6 Mesa 21.3.5
Audio:     Device-1: Intel Cannon Point-LP High Definition Audio driver: snd_hda_intel
           Sound Server-1: ALSA v: k5.16.5-1-default running: yes
           Sound Server-2: PulseAudio v: 15.0 running: yes
           Sound Server-3: PipeWire v: 0.3.45 running: yes
Network:   Device-1: Intel Cannon Point-LP CNVi [Wireless-AC] driver: iwlwifi
           IF: wlp0s20f3 state: down mac: 8a:df:2c:8e:39:23
           Device-2: Intel Ethernet I219-V driver: e1000e
           IF: eno1 state: up speed: 100 Mbps duplex: full mac: 1c:69:7a:00:6a:55
           IF-ID-1: virbr0 state: down mac: 52:54:00:8d:11:34
Bluetooth: Device-1: Intel Bluetooth 9460/9560 Jefferson Peak (JfP) type: USB driver: btusb
           Report: rfkill ID: hci0 state: up address: see --recommends
Drives:    Local Storage: total: 931.51 GiB used: 50.93 GiB (5.5%)
           ID-1: /dev/sda vendor: Samsung model: SSD 860 EVO 1TB size: 931.51 GiB
Partition: ID-1: / size: 913.35 GiB used: 50.92 GiB (5.6%) fs: ext4 dev: /dev/sda2
           ID-2: /boot/efi size: 511 MiB used: 4.8 MiB (0.9%) fs: vfat dev: /dev/sda1
Swap:      ID-1: swap-1 type: partition size: 2 GiB used: 0 KiB (0.0%) dev: /dev/sda3
Sensors:   System Temperatures: cpu: 48.0 C mobo: 27.8 C
           Fan Speeds (RPM): N/A
Info:      Processes: 273 Uptime: 0h 30m Memory: 7.62 GiB used: 2.07 GiB (27.2%) Shell: Bash inxi: 3.3.07
raija@localhost:~> inxi -G
Graphics:  Device-1: Intel CoffeeLake-U GT3e [Iris Plus Graphics 655] driver: i915 v: kernel
           Display: x11 server: X.Org 1.21.1.3 driver: loaded: modesetting unloaded: fbdev,vesa resolution: 1920x1080~60Hz
           OpenGL: renderer: Mesa Intel Iris Plus Graphics 655 (CFL GT3) v: 4.6 Mesa 21.3.5


GUEST:
mint@mint:~$ inxi -F
System:
  Host: mint Kernel: 5.4.0-99-generic x86_64 bits: 64 
  Desktop: Cinnamon 5.2.7 Distro: **Linux Mint 20.3 Una** 
Machine:
  Type: Kvm System: QEMU product: Standard PC (Q35 + ICH9, 2009) 
  v: pc-q35-6.2 serial: <superuser/root required> 
  Mobo: N/A model: N/A serial: N/A BIOS: SeaBIOS 
  v: rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org date: 04/01/2014 
CPU:
  Topology: 2x Single Core model: Intel Core (Skylake IBRS) bits: 64 
  type: SMP L2 cache: 32.0 MiB 
  Speed: 2712 MHz min/max: N/A Core speeds (MHz): 1: 2712 2: 2712 
Graphics:
  Device-1: Red Hat QXL paravirtual graphic card driver: qxl v: kernel 
  Display: x11 server: X.Org 1.20.13 driver: none 
  unloaded: fbdev,modesetting,**vesa resolution: 1024x768~60Hz** 
  OpenGL: renderer: llvmpipe (LLVM 12.0.0 256 bits) v: 4.5 Mesa 21.2.6 
Audio:
  Device-1: Intel 82801I HD Audio driver: snd_hda_intel 
  Sound Server: ALSA v: k5.4.0-99-generic 
Network:
  Device-1: Red Hat Virtio network driver: virtio-pci 
  IF-ID-1: enp1s0 state: up speed: -1 duplex: unknown mac: 52:54:00:b5:e2:9c 
Drives:
  Local Storage: total: 20.00 GiB used: 9.11 GiB (45.5%) 
  ID-1: /dev/vda model: N/A size: 20.00 GiB 
Partition:
  ID-1: / size: 19.07 GiB used: 9.11 GiB (47.8%) fs: ext4 dev: /dev/vda5 
Sensors:
  Message: No sensors data was found. Is sensors configured? 
Info:
  Processes: 185 Uptime: 1m Memory: 3.84 GiB used: 686.1 MiB (17.5%) 
  Shell: bash inxi: 3.0.38 
mint@mint:~$

I have installed QEMU / KVM in openSUSE Tumbleweed (HOST) and Linux Mint 20.3 (GUEST) on it. When I start Linux Mint, the screen resolution is set to 1024x768 (4:3) by default. I’d like to change default resolution as 1600x900 (16:9).

What files should I patch and how?

URL: https://paste.opensuse.org/94964203

2

Hi
On the guest if you use xrandr -s <your resolution> does this change it? If not might want to try some of the other guest graphics driver options.

3

Try virtio for your guest video. I run that on all my linux/windows guests and it does work well.

4

The command you enter changes the resolution without any problems, but the configuration does not remain, but is the same as before (1024x768).

5

Do you mean I’m switching from a Spice screen to a VNC screen? However, I will try that.

I tested that Spice -> VNC switch. Did not work at all.

6

Hi
There must be a guest desktop setup to define the resolution if xrandr works?

7

Yes, the resolution can be changed in Desktop, but it won’t be saved (or at least I can’t). When I change the resolution, I get error messages that I don’t understand.
I’ll take a screenshot of the error messages as soon as I can.

Here are the erromessage:

URL: SUSE Paste

asetusten käyttöönotto epäonnistui = settings failed
tuntematon = unknown

8

Hi
So if xrandr and the settings work but aren’t saved I would suspect the guest is the issue. Might pay to ask on the Mint forums? Else can always add the xrandr -s command to your ~/.profile to set on login, but that’s a workaround, not a fix.

Maybe even adding the settings to boot grub kernel options video=1600x900@60 and rebuild Mint grub may help…

9

Thank you very much again.

I try to make that patch first and if I don’t make it work, I ask the Mint forum.

10

No, switch from video QXL to virtio.
https://paste.opensuse.org/2868853

11

It’s just like you first said. I must be blind!

Now I can define the resolution as I want and the settings will remain over the reset.