Hi Jan, > Why? Ahh, because of qemu_cpu_kick_self: raise(SIG_IPI)! That should > generate a per-process SIG_IPI. And that may not only affect Darwin. > Looks good.
Actually, with io-thread enabled, it goes through qemu_cpu_kick_self() -> qemu_cpu_kick_thread() -> pthread_kill(..., SIG_IPI). I think the problem is with sigwait(). It doesn't state so in the Linux or Darwin man pages, but on Solaris, it says : "All signals identified by the set argument must be blocked on all threads, including the calling thread; otherwise, sigwait() might not work correctly", which might correspond to the issue I've been witnessing (ie: sigwait() unblocking once in a while on a SIGUSR1 (SIG_IPI) in the event thread). In any case, I don't think it should attempt to catch this signal at all since the cpu thread is already catching it. Alexandre
