Got this when I tried to run hal-trinity manually:

Nov 2 10:25:03 toto kernel: [ 6448.428655] hald[3942]: segfault at 0 ip

000000000041059b sp 00007fff40a1d690 error 4 in hald[400000+52000] Nov 2 10:25:03 toto init: hal-trinity main process (3942) killed by SEGV signal

<snip>

There is no way to run 3.5.12 on Natty without a reinstall, and even then you will probably run into some odd dependency problems.

My suggestion is this: 1. Use dpkg --purge --force-all to remove all hal related packages (i.e. all packages with hal in their name; use dpkg -l | grep hal to find them) 2. apt-get update 3. apt-get -f install 4. Reboot

I have seen the HAL files end up in an inconsistent state on distribution upgrades before, which causes all kinds of havoc in HAL-dependent programs. This sequence has always fixed the problem for me.

Tim