On 07/05/2018 12:06 PM, Greg KH wrote:
On Thu, Jul 05, 2018 at 12:05:09PM -0400, Andrey Grodzovsky wrote:
This patch is wrong as noted by MIchel a while ago - quote from his review
of the patch.
"Actually, pflip_status should really only be set to AMDGPU_FLIP_SUBMITTED
after the flip has been programmed to the hardware, at least as far as the
lock holder is concerned. That's why the code was previously holding the
lock until after the dc_commit_updates_for_stream call. Otherwise, it's at
least theoretically possible that either:
* dm_pflip_high_irq is called before dc_commit_updates_for_stream, but sees
flip_status == AMDGPU_FLIP_SUBMITTED and sends the event to userspace
prematurely
* dm_pflip_high_irq is called after dc_commit_updates_for_stream, but sees
flip_status != AMDGPU_FLIP_SUBMITTED, so it incorrectly doesn't send the
event to userspace "
It shouldn't go in.
Is there a fix for this in Linus's tree for these problems?
If not, why not? If so, what is that git commit id?
AFAIK there is still no fix for the original issue which this patch was
intended to fix.
Harry, can you please comment on this ?
Andrey
thanks,
greg k-h
