Comment 18 for bug 477106

If I interpret this thread correctly, the "fix" was adding the sysfs parameter to allow designating the cards as non-removable. By setting the parameter to "N", it should be possible to suspend with a card mounted. But I do not observe this to be the case:

To reproduce:
1. Boot.
2. Log in.
3. Open a terminal:

khaeru@khaeru-laptop:~$ apt-cache policy linux-image-generic
linux-image-generic:
  Installed: 2.6.32.21.22
  Candidate: 2.6.32.21.22
  Version table:
 *** 2.6.32.21.22 0
        500 http://archive.ubuntu.com/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status
khaeru@khaeru-laptop:~$ cat /sys/module/mmc_core/parameters/removable
Y
khaeru@khaeru-laptop:~$ echo N | sudo tee /sys/module/mmc_core/parameters/removable
[sudo] password for khaeru:
N
khaeru@khaeru-laptop:~$ cat /sys/module/mmc_core/parameters/removable
N
khaeru@khaeru-laptop:~$ sudo pm-suspend

Observed:
* Hard disk LED illuminates for several seconds.
* Computer freezes: video remains on-screen, power LED green ('on'), unresponsive to all input.

Expected:
* Computer suspends.