[PATCH] drm/ttm: Don't inherit GEM object VMAs in child process

[Felix Kuehling]

Am 2022-01-05 um 11:16 a.m. schrieb Felix Kuehling:
>> I was already wondering which mmaps through the KFD node we have left
>> which cause problems here.
> We still use the KFD FD for mapping doorbells and HDP flushing. These
> are both SG BOs, so they cannot be CPU-mapped through render nodes. The
> KFD FD is also used for mapping signal pages and CWSR trap handlers on
> old APUs.
>
> Those VMAs aren't causing the problem. They still map successfully on
> restore.
>
>
Small correction: KFD already sets the VM_DONTCOPY flag for all KFD FD
mappings.

The patch under discussion here does the same for DRM FD mappings (at
least for KFD BOs).

Regards,
  Felix