Comment 46 for bug 251252

Mathieu is correct; the best solution would be to remove l-b-m. I, however, need l-b-m to fix bug 259904.

The downsides of editing the sleep.d hook are two-fold:

  * Buggy network drivers may be unable to handle suspending and may cause all kinds of problems (from network no longer working after a resume to system crashes). It depends on the drivers loaded, which depend on your hardware. In my case I have two network drivers loaded: e1000 and iwl3945. Both appear to handle suspend correctly without unloading and reloading the module. Actually, I haven't tried using wired network after a resume, but at least there are no crashes on suspend.

  * Having a modified sleep.d hook may cause problems in the future when you upgrade your OS. Your modified hook will override whatever the new Ubuntu version ship, which may cause suspend problems. This is not very likely, but possible, and something to keep in mind. It'd be best to remove the copy in /etc/pm/sleep.d before you upgrade to 8.10. Actually, it's best to remove it as soon as you no longer need it -- i.e. when a new linux-backports-modules release fixes the kernel panic on rmmod.

(Somewhat ironically, removing of network modules before suspending is also a workaround, and not a proper solution, AFAIU. Drivers are supposed to handle suspend correctly by putting the hardware into the appropriate sleep state etc. Except that buggy ones don't, and so far it's easier to make suspend work by removing the modules rather than debugging and fixing all the buggy drivers.)