Montag, 6. Juli 2009

Driver bugs (and how quick they _can_ fixed)

Recently I found exactly the same driver bug in RadeonHD on my RadeinHD3850, I've reported for <= Intel-945 about almost a year ago. The bug probably would not be worth mentioning it, however Tungstengraphic's Roland Scheidegger fixed the bug 3 weeks after I've reported it.

The problem seems to be an off-by-one-half problem, causing images which are scaled on the x-axis to be also blurred on the y-axis. The first line is rendered with pixman (reference), the second with Intel-2.8.0pre on my i945GM:
No big deal, unfourtunatly it makes Nimbus look pretty ugly :-(

There is quite a long list of driver bugs and performance problems I reported against the Intel driver in the freedesktop bugzilla. So far a single pipeline related bug has been fixed (and only for i965 and up, not for the i945 I call my own). Even for bugs causing image rendering corruptions in firefox nothing happens.
Despite the fact that the last two stable releases (2.6 & 2.7) can hardly be called "stable" and are driving distributors crazy, there are major performance regressions.

Hopefully that problems will be resolved soon, however time told a different story in the past.


shamaz hat gesagt…

Maybe it would be possible to create some automated tests to compare the rendering of the driver with a reference ?
This would help driver developpers to find bugs easily, and avoid regression.
Of course... this should be _their_ work but still.

Linuxhippy hat gesagt…

Yes, an automated test suite for correctness testing would be great.

However in Intel's case it wouldn't change a thing. They don't fix known bugs, why should they be interested in discovering new bugs ;)