SIGBUS with gbm_bo_map() and Intel ARC

[Pierre Ossman]

On 6/19/24 11:36, Pierre Ossman wrote:
> 
> Is there something special I need to pay attention to when doing cross 
> GPU stuff? I would have assumed that gbm_bo_import() would have 
> complained if this was an incompatible setup.
> 

It does indeed look like some step is missing. If I examine 
/proc/<pid>/maps, I can see that the accessed memory address is 
associated with the wrong render node:

Crash reading 0x7fffe4176000
7fffe4176000-7fffe4400000 rw-s 100602000 00:06 500 
/dev/dri/renderD128

The X server is using renderD128, but the client is using renderD129.

This works with other X servers, so I assume there is some way to 
resolve this. But where do I start looking?

The fd I'm getting is a DMA-BUF fd, I assume? I can't find many ioctls 
for that. But that's also all I'm getting, so there must be something 
I'm supposed to do with that fd?

Help! :/

Regards
-- 
Pierre Ossman           Software Development
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