2.6.37-rc7: screen black after several suspends

Good morning guys,

with 2.6.37-rc7 automatic wifi reconnect works, but after several suspend and resume issues the screen stays black. I am running Linux on the Lenovo X201, Intel graphics card [0].

Earlier kernel versions (around 2.6.35, iirc) sometimes allowed me to restore it by switching away from X to the console, which stopped working broken display (weired characters everywhere) after some time.

With 2.6.37-rc7 this does not work. After about 4-5 suspends the screen stays black, the machine is still working otherwise (i.e. rebooting it works fine).

It seems there's a long ongoing problem restoring the display, seeing it in various forms (including freeze) in at least

* 2.6.27-rc1-00156-g94ad374,
* 2.6.28-next-20090107-ikn
* 2.6.28-ikn-06859-gede6f5a
* 2.6.28-rc9-wl-ikn-24949-ge98df74
* 2.6.29-rc4-58-g4c098bc,
* 2.6.29-rc5-ikn-00168-gba95fd4
* 2.6.30-rc7
* 2.6.31-r2
* many many more, see messages from me to LKML

With some working version (just brighness related):

* 2.6.29-rc7-wl-ikn-32831-g98c5597
* 2.6.30-rc3-next-20090428-04067-g72f1b63

I'm wondering whether there

a) is one bug coming up again and not really fixed
b) are many bugs, just parts fixed
c) new bugs are introduced quite often

In any case, I downgraded to 2.6.36-ARCH, which works fine related to brightness and suspend/resume.

Cheers,

Nico

[0] 00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02).

PGP key: 7ED9 F7D3 6B10 81D7 0EC5  5C09 D7DC C8E4 3187 7DF0

Hey devs,

Just for the record:

Some tens of SUCCESSFUL suspends & wakeups on 2.6.37-rc8-00033-gb518a64.

Xorg crashed once (black screen, not recoverable with tty switching), restarted it, still works. Even with some lazy umounted nfs mounts, even with LUKS devices / usb being used during suspend and removing on wakeup.

This is probably the most stable kernel version I've seen in a long time!

Cheers,

Nico

PGP key: 7ED9 F7D3 6B10 81D7 0EC5  5C09 D7DC C8E4 3187 7DF0