Nathan Lynch wrote: > (very rfc for now, no sign-off, needs more testing) > > There are a couple of bugs in the rtas_ibm_suspend_me() and > rtas_percpu_suspend_me() functions: > > 1. rtas_ibm_suspend_me() uses on_each_cpu() to invoke > rtas_percpu_suspend_me() via IPI: > > if (on_each_cpu(rtas_percpu_suspend_me, &data, 1, 0)) > ... > > 'data' is on the stack, and rtas_ibm_suspend_me() takes no measures to > ensure that all instances of rtas_percpu_suspend_me() are finished > accessing 'data' before returning. This can result in the IPI'd cpus > accessing random stack data and getting stuck in H_JOIN.
Another possible issue is that H_JOIN requires MSR.EE to be off, but lazy interrupt disabling could conceivably allow that constraint to be violated if we end up doing H_JOIN on the cpu which calls on_each_cpu(). At least I think so... _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
