kern/49722: drm: radeon: mpv stopped working

[Thomas Klausner <wiz%NetBSD.org@localhost>]

>Number:         49722
>Category:       kern
>Synopsis:       drm: radeon: mpv stopped working
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 05 17:20:00 +0000 2015
>Originator:     Thomas Klausner
>Release:        NetBSD 7.99.5
>Organization:
Curiosity is the very basis of education and if you tell me that 
curiosity killed the cat, I say only that the cat died nobly.
- Arnold Edinborough
>Environment:
	
	
Architecture: x86_64
Machine: amd64
>Description:
The recent fixes for DRM and radeon made the artifacts vanish for me, but
on the other multimedia/mpv stopped working. mplayer still works fine on
the same files.

mpv writes:

drmRadeonCmdBuffer: -22. Kernel failed to parse or rejected command stream. See dmesg for more info.   

and dmesg contains:
radeon0: warning: r600_cs_track_validate_cb:419 cb height (1080, 0x20, 4) invalid
radeon0: warning: r600_packet3_check:1737 invalid cmd stream 484
DRM error in radeon_cs_ib_chunk: Invalid command stream !

Chipset from xorg.0.log:
[    63.176] (--) RADEON(0): Chipset: "ATI RV730 PRO [Radeon HD 4650]" (ChipID = 0x9498)
>How-To-Repeat:
mpv any.file.mp4
>Fix:
please.

>Unformatted: