Qemu/sdl problems

Created by: robinpaulson

I updated to the latest pmbootstrap today and tried building for qemu-amd64.

This had worked previously, I perhaps last did it two weeks ago.

This appears to be the problem: DL1 display code has no opengl support. Please recompile qemu with SDL2, using ./configure --enable-sdl --with-sdlabi=2.0

I got this with the stock qemu (v2.5) in Ubuntu 16.04. I gather from other issues here that there have been some changes recently in how pmb handles sdl/opengl, etc.

Created by: PureTryOut

Since #861, Qemu now runs with the Virtio drivers to enable 3D hardware acceleration on x86_64. This change required us to launch Qemu with either an SDL or a GTK window. Out of my own tests, the SDL window worked the best and it also had the least amount of dependencies, so we went with it.

To be honest, I expected every major distro to have Qemu compiled with SDL enabled, I guess this is not the case. As a workaround you can choose the dri-swrast driver in ./pmbootstrap.py init for now. It'll remove the SDL dependency, but disable 3D hardware acceleration.

Could you try and see if the GTK interface works for you? You can copy the command pmbootstrap uses from ./pmbootstrap.py log if you run ./pmbootstrap.py qemu. Replace -display sdl,gl=on with -display gtk,gl=on. Just run it in a separate terminal.

By * postmarketOS Bot on 2017-11-14T13:26:50

Created by: ollieparanoid

In fact, you can supply the display parameter to pmbootstrap qemu now, for example:

pmbootstrap qemu --display=gtk,gl=on
pmbootstrap qemu --display=gtk,gl=off

Furthermore you can choose the swrast mesa driver again, if this still doesn't work for you. pmbootstrap init asks which mesa driver you want to use.

Sorry for the regression though. The plan is, that we use the qemu binaries supplied by Alpine Linux instead of the ones from the host distribution in the long term, so we have the same feature-set everywhere.

By * postmarketOS Bot on 2017-11-14T23:07:47

Created by: robinpaulson

Great, cheers for the suggestions. I'll try specifying the display parameter first and see where that gets me.

As an aside, I'm slightly surprised to see qemu built without a relevant option. I even tried a later version (2.6) from a ppa but got the same errors. I guess I'm only using qemu for testing, so it's not a big problem. As you say, the binaries in Alpine are what's important.

By * postmarketOS Bot on 2017-11-14T22:46:06

Created by: robinpaulson

Hmm, now this: qemu-system-x86_64: -display gtk,gl=on: GTK support is disabled when I run $ pmbootstrap qemu --image-size=2G --display=gtk,gl=on

By * postmarketOS Bot on 2017-11-15T00:29:28

Created by: PureTryOut

Yeah so just use the dri-swrast driver and don't manually specify a display to use.

By * postmarketOS Bot on 2017-11-15T09:38:37

Created by: ollieparanoid

The way it works now, it will always pass a display parameter to Qemu (no matter which mesa driver you choose). The only exception is SPICE, see below. You can check which values for display your qemu version supports with: qemu-system-x86_64 --help | grep display

-h or -help     display this help and exit
-version        display version information and exit
-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]
-display gtk[,grab_on_hover=on|off][,gl=on|off]|
-display vnc=<display>[,<optargs>]
-display curses
-display none                select display type
The default display is equivalent to
        "-display gtk"
-curses         shorthand for -display curses
-sdl            shorthand for -display sdl
       [,tls-channel=[main|display|cursor|inputs|record|playback]]
       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]
-vnc <display>  shorthand for -display vnc=<display>

"The default display..." text is especially relevant.

If all else fails, we also provide pmbootstrap qemu --spice, where the output is done by a SPICE client instead of Qemu. (You'll either need to have remote-viewer or spicy installed as clients and they get started automatically.)

By * postmarketOS Bot on 2017-11-15T16:09:50

Created by: ollieparanoid

So this seems to be a problem with the Qemu version of your host system, and not with pmbootstrap. In addition nothing happened here since two months, so I'm closing this issue.

Just tell us if you need more support with this issue, then we can reopen it.

By * postmarketOS Bot on 2018-01-20T01:50:01

Created by: techgnosis

ollieparanoid can you tell us what distro you are using since Ubuntu/Mint doesn't appear to be compiling qemu with SDL or GTK support?

By * postmarketOS Bot on 2018-01-23T04:48:33

Created by: ollieparanoid

Arch Linux. But the real fix would be having one good version in Alpine, that we can all use. Opened #1158 (closed) to track this.

By * postmarketOS Bot on 2018-01-23T21:41:21