Re: 2.6.33 bugs (USBFS, Intel graphic)

[Markus Rechberger <mrechberger@gmail.com>]

On Sat, Feb 27, 2010 at 7:08 PM, Markus Rechberger
<mrechberger@gmail.com> wrote:
> On Sat, Feb 27, 2010 at 5:49 PM, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
>> On Sat, 27 Feb 2010 14:17:14 +0200
>> Pekka Enberg <penberg@cs.helsinki.fi> wrote:
>>
>>> On Sat, Feb 27, 2010 at 2:15 PM, Pekka Enberg
>>> <penberg@cs.helsinki.fi> wrote:
>>> > On Sat, Feb 27, 2010 at 1:00 PM, Markus Rechberger
>>> > <mrechberger@gmail.com> wrote:
>>> >>> Linus, I know you didn't want to do a kzalloc, but it looks like
>>> >>> this is the easiest/simplest thing to do, unless you can think of
>>> >>> something else?
>>> >>
>>> >> do you have any idea what to cherrypick in order to get rid of that
>>> >> flickering with the intel GM45?
>>> >> The flickering itself occures randomly, it was not there with the
>>> >> original Ubuntu kernel (2.6.31 with alot patches)
>>> >> This is pretty much a standard graphicchip nowadays....
>>> >
>>> > Yeah, same here. I tried to bisect the damn thing but didn't find
>>> > any single commit. I think the problem was introduced in in the DRM
>>> > merge between 2.6.31 and 2.6.32-rc1. Some people suggested
>>> > privately that it might be related to frame buffer compression.
>>> > Unfortunately I wasn't able to revert that particular patch.
>>>
>>> Btw, after I reinstalled Ubuntu 9.10 from scratch for unrelated
>>> reasons, I haven't seen the flicker effect. Dunno if that's just a
>>> coincidence or if userspace has something to do with the bug.
>>
>> Some people reported ACPI related flicker due to lid detection taking a
>> long time and X periodically probing for it.  Maybe that's what you
>> were seeing?
>>
>
> little bit offtopic there's another bug with the intel driver. Seems
> like there's a memory pool which collects all the memory during the
> runtime and especially makes the memory usage go up:
> http://bugs.freedesktop.org/show_bug.cgi?id=26708
> Maybe someone at Intel can have a closer look at that one...
>
> another obvious bug seems to be offloading mpeg2 video to the GPU it
> takes more CPU than decoding mpeg2 with software. Offloading is quite
> important nowadays due HDTV. The only one which has working linux
> support is NVidia with their closed source drivers.
>

Intel Graphic seems to be the pure chaos with Linux ....
I booted the old kernel again and did some debugging because the load
of udevd sometimes goes up.. the netlink interface seems to flood udev
with following message with ubuntu karmic 2.6.31
LINE: change@/devices/pci0000:00/0000:00:02.0/drm/card0
LINE: ACTION=change
LINE: DEVPATH=/devices/pci0000:00/0000:00:02.0/drm/card0
LINE: SUBSYSTEM=drm
LINE: HOTPLUG=1
LINE: MAJOR=226
LINE: MINOR=0
LINE: DEVNAME=dri/card0
LINE: DEVTYPE=drm_minor
LINE: SEQNUM=47819

obviosly this seems to be solved with the newer kernel, but there we
have that flickering issue and OpenGL support is messy

Aside of that some people sent me emails offlist that intel stopped
working correctly for them starting from 2.6.27 on. Is anyone from
Intel still working on the graphicdriver?

Some of our business customers are now switching to HDTV compatible
systems and Intel seems to be a nogo right now, NVidia Tegra seems to
have potential.

Markus