Suspend / Resume problem with -ck kernels.

Question

Sometimes with the linux-ck kernel my laptop doesn't suspend / resume correctly.
Sometimes when suspending my laptop will take "extra long" to suspend.
When it resumes the processor & fan will turn on, but the suspend light will still be blinking and the screen doesn't turn on.  Sometimes (but not always) the caps-lock light will start blinking after I try to wake it up, like a kernel panic. It happens more often when closing the lid to suspend, but has happened while suspending manually.
This only happens with -ck kernels. I have tried both the linux-ck and linux-ck-corex kernels with same result. This started happening around kernel 3.0.8 I believe. I thought it was a bug that would be fixed, but it still occurs.
I have a Lenovo Thinkpad T410s,  Intel Core i5, Intel graphics. I use the TLP scripts for power savings, and Xfce-Power-Manager for my power manager. I can see nothing relevant in the logs. Suspend / Resume always works with the "official" kernel.
Any ideas?

Answer 1

Ok, I think I narrowed the problem down to the BFS scheduler.
I compiled "linux-bfs" from the AUR, installed it and rebooted and lo and behold my suspend / resume problem was back. Rebooted with the stock kernel, did about 10 suspend & resume cycles in a row... and it worked great each time.
Sometimes when using linux-bfs or linux-ck, I can "revive" the system after a bad resume, by closing the lid and opening it slowly. Also I know the screen is just not "off", because the caps lock key light will not respond. If the caps-lock key light starts blinking (on-and-off) after a resume, I assume it is a kernel panic, and nothing besides a forced power-off will fix it.
Last edited by jon (2011-12-09 18:11:27)