The macbook pro 5,1 model no longer boots with acpi enabled. I can only get my system to boot with acpi=off. I tried kernel 2.6.33 and everything seems to work. When using 2.6.34 my system hangs at waiting for udev uevents to be processed. I'm trying to figure out how I can get more info. I will also try 2.6.35-rc3.
I'm not aware of any 2.6.34 regressions like this. can you use git-bisect to find out which commit introduces this bug? cc Rafael, as this should be on 2.6.34 regressions list.
I can try, I have no experience with git though.
lots of git bisect howto's, like this one: http://ivanz.com/2009/03/27/git-bisect-the-awesome-way-to-find-the-mr-bug-commit/ also, the man page itself: http://www.kernel.org/pub/software/scm/git/docs/git-bisect.html One guess would be drivers/acpi/ec.c so you might do something simple like limit the bisect to that file, or to drivers/acpi/
I'm not sure if I built my kernels correctly using git bisect. I used my distributions kernel config file when I was building my kernels, but I stripped the config down a little, because it was building a lot of stuff I didn't need as modules. After going through all the git bisect steps and having each kernel work, I realized the problem must be in one of the things I didn't build as a module. So, this either might not be an upstream problem, or it might not be an acpi problem, because I was able to get my system to boot with acpi enabled with every single git bisect kernel.