Comment 27 for bug 594837

Sorry to comment on a fixed bug, but my problem seems to be closely related. My system is Dell Latitude e6410 with Intel i7.

Resume from suspend to memory was not working for me on kernels prior 2.6.36. Since 2.6.36 it works flawlessly but only when resuming with AC adapter plugged-in.

When resuming on batteries (no matter whether previously suspended on AC or batteries) the system completely hangs - either on first attempt or usually on 2nd or 3rd or at max a 5th attempt of sequential suspend/resume cycles.

No success tweaking with /etc/pm/* and /usr/lib/pm-utils/* disabling there actions related to current computer power source.

Finally disabling CPU speed-step in BIOS resolved the problem. Tested with success on 20 sequential suspend/resume cycles on battery power. Evidently this a workaround which is killing the battery :/

I'm not sure what *exactly* the script /usr/lib/pm-utils/sleep.d/94cpufreq is about, but disabling it had no effect. I don't have enough knowledge to perform advanced tests with CPU scaling and governors.