Michel Dänzer michel@daenzer.net writes:
Subtle breakage here: vblwait->request.sequence must still get updated for _DRM_VBLANK_RELATIVE, in case we're interrupted by a signal.
Thanks for finding this.
I think it might be better to just not modify the request.type field instead, so that on re-entry it gets recomputed? That would mean that a signal might cause the value to be different if the application takes a long time processing the signal, but I'm not sure that's wrong?
@@ -317,6 +317,9 @@ int via_driver_irq_postinstall(struct drm_device *dev) if (!dev_priv) return -EINVAL;
- if (dev->driver->get_vblank_counter)
dev->max_vblank_count = 0xffffffff;What's the purpose of this? All drivers providing get_vblank_counter should already initialize max_vblank_count correctly.
Yeah, I couldn't prove that this driver did that, and as Daniel says, we haven't ever audited the drivers to make sure they do.
We have a check to see that they don't set max_vblank_count if they don't provide a get function, but I can't find the matching check for drivers that do provide a function and aren't setting max_vblank_count.
Do you have any thoughts on the wisdom of changing this API before we have a driver that needs it?
And, of course, thanks for your review!