All-black X windows with etnaviv/xwayland/glamor

Michel Dänzer michel at
Wed Feb 14 09:13:04 UTC 2018

On 2018-02-13 07:34 PM, Lukas F. Hartmann wrote:
> Michel Dänzer <michel at> writes:
>> On 2018-02-13 04:23 PM, Lukas F. Hartmann wrote:
>>> - Xwayland/glamor registers its gbm buffer with wl_drm_create_prime_buffer (passing a fd) which ends up in drm_create_prime_buffer on the server side. I might have made mistakes, but when mapping the gbm_bo on that side (using gbm_bo_import and then gbm_map_bo), it appears that the buffer is empty (maybe it cannot be transferred correctly?).
>> Unless there's a dma-buf API usage mistake in userspace, it sounds like
>> a kernel issue, since the two processes are seeing different contents in
>> what should be one and the same BO.
>> Can you test Xorg with DRI3? Do OpenGL apps work correctly with that?
> I just rebuilt Xorg and started it with a minimal modesetting conf:
> - with AccelMethod "none", I get a working/visible unaccelerated desktop,
>   glxinfo showing softpipe
> - with AccelMethod "glamor", I get an invisible desktop (possibly same problem as
>   in Xwayland). DRI3 is enabled which I confirmed by stepping with gdb
>   through glamor_egl_screen_init. glxinfo shows "Vivante GC3000 rev
>   5450" and "Max compat profile version: 2.1.", glxgears has a high
>   framerate. But I cannot see any of this output.

That seems to confirm a kernel issue. The (unlikely) alternative is that
you've discovered a long standing bug in the dma-buf related userspace
code, which doesn't affect other platforms.

Earthling Michel Dänzer               |     
Libre software enthusiast             |             Mesa and X developer

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