Bug#689268: Intel HD 4000 (Ivy Bridge) graphics freeze

[Ingo <ingo.steiner@gmx.net>]

Am 21.10.2012 14:20, schrieb Per Foreby:

> [    22.177] (II) VESA(0): Total Memory: 1023 64KB banks (65472kB)
> [    22.200] (II) VESA(0): VESA VBE Total Mem: 65472 kB
> 
> Note that this is 1023 memory banks, not 1024, so it's not exactly 64 MB
> (65536 kB). Maybe the reason why it almost works with 256 MB is that the
> kernel always thinks that we have exactly 256 MB but the Mobo supplies
> one memory bank less. Just a theory..

I checked here (with 256MB VideoRAM set in BIOS and i915 loaded) - all
is stable now.
dmesg says:
...
[    0.985848] agpgart-intel 0000:00:00.0: detected 65536K stolen memory
...

Don't know where they have gone or who did reserve them. Maybe thats
what Intel's "Dynamic Video Memory Technology (DVMT)" uses?

Isn't there anybody out who has more insight into this issue and could
give some explanation how things should work and give hints how to pin
that down?