On 1/10/07, Balbir Singh <balbir at in.ibm.com> wrote: > > I have run into a problem running this patch on a powerpc box. Basically, > the machine panics as soon as I mount the container filesystem with This is a multi-processor system? My guess is that it's a race in the subsystem API that I've been meaning to deal with for some time - basically I've been using (<foo>_subsys.subsys_id != -1) to indicate that <foo> is ready for use, but there's a brief window during subsystem registration where that's not actually true. I'll add an "active" field in the container_subsys structure, which isn't set until registration is completed, and subsystems should use that instead. container_register_subsys() will set it just prior to releasing callback_mutex, and cpu_acct.c (and other subsystems) will check <foo>_subsys.active rather than (<foo>_subsys.subsys_id != -1) > I am trying to figure out the reason for the panic and trying to find > a fix. Since the introduction of whole hierarchy system, the debugging > has gotten a bit harder and taking longer, hence I was wondering if you > had any clues about the problem > Yes, the multi-hierarchy support does make the whole code a little more complex - but people presented reasonable scenarios where a single container tree for all resource controllers just wasn't flexible enough. Paul