Re: [PATCH 1/3] drm/amd: fix race in page flip job

From: Michel DÃnzer
Date: Fri Dec 21 2018 - 03:57:01 EST


On 2018-12-21 4:10 a.m., Yu Zhao wrote:
> Fix race between page flip job submission and completion. We invoke
> page_flip callback to submit page flip job to GPU first and then set
> pflip_status. If GPU fires page flip done irq in between, its handler
> won't see the correct pflip_status thus will refuse to notify the job
> completion. The job will eventually times out.
>
> Reverse the order of calling page_flip and setting pflip_status to
> fix the race.

There is no race, amdgpu_crtc->pflip_status is protected by dev->event_lock.


--
Earthling Michel DÃnzer | http://www.amd.com
Libre software enthusiast | Mesa and X developer