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dragon321

Member

Registered: 2016-01-24

Posts: 21

virglrenderer - black screen with buffer error

Hello everyone.

A few months ago I could use qemu with virtio gpu without problems. Now It seems it's broken. I tried two Linux distributions (Arch Linux and Gears on Gallium) as guest, and both have same issue. Let me explain it:
I run qemu with these options (i try GoG, but Arch guest has same issue):

qemu-system-x86_64 -enable-kvm -m 2048 -vga virtio -display gtk,gl=on -cdrom Gears_on_Gallium.x86_64-16.11.13.iso

it works without errors, but when guest shows login screen, error appears on terminal output:

vrend_report_buffer_error: context error reported 1 "X" Illegal command buffer 87098369

and virtual machine screen becomes black (I can still use guest, so machine doesn't stop working, only rendering is broken).

What I tried to do:
1. Compile qemu from git
2. Compile mesa from git
3. Compile virglrenderer from git

Nothing helped. Always same issue. Any ideas?

onslow77

Member

Registered: 2014-09-21

Posts: 279

Re: virglrenderer - black screen with buffer error

What I tried to do:
1. Compile qemu from git
2. Compile mesa from git
3. Compile virglrenderer from git

Nothing helped. Always same issue. Any ideas?

Why are compiling "qemu, mesa, and virglrenderer" from git? All of the packages are in Arch "Extra" repository or AUR, see:
- QEMU
- mesa
- virglrenderer_in_extra and virglrenderer_in_AUR

Regards
Martin

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It is advised to follow the How to post guide when posting on the Arch forum. If one consciously jumps over these elementary steps like reading the wiki and providing necessary information about the problem, one can be regarded as a Help Vampire.

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: virglrenderer - black screen with buffer error

@dragon321
Have you tried with the stock arch packages but using the lts kernel?

@onslow77
Because if the problem is in one of those packages, sometimes a fix is already included in the git version and just waiting to be released in a stable version.

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R00KIE
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dragon321

Member

Registered: 2016-01-24

Posts: 21

Re: virglrenderer - black screen with buffer error

@onslow77
You don't understand - I had normal packages from repo, but I tried to compile git version to check if this help.

@R00KIE
Yes, I tried - forgot to write, sorry. Same issue. I tried on stock packages and git - always same issue.

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: virglrenderer - black screen with buffer error

Best I could find was this https://lists.gnu.org/archive/html/qemu … 03964.html where it says:

> vrend_report_buffer_error: context error reported 3 "Xorg" Illegal
> command buffer 149816321

This is a virglrenderer bug, translating a shader. You could try with
virglrenderer from git, and if it still fails, report a bug to the virgl
mailing list.

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R00KIE
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dragon321

Member

Registered: 2016-01-24

Posts: 21

Re: virglrenderer - black screen with buffer error

@R00KIE: I found it too. virglrenderer-git has same issue. Well, I should write on they mailing list.

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: virglrenderer - black screen with buffer error

Asking on the mailing list first is a good idea, but also check if there are any bug reports open about this. If there are no bug reports open you should open a new one after asking on the mailing list, otherwise this problem might be put on hold until more people have this problem (once other distros move to more recent software versions).

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R00KIE
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