On 31 July 2014 18:21, Paolo Bonzini <pbonz...@redhat.com> wrote: > What does ARM do if you have a WFI while interrupts are disabled? On > x86 after "cli;hlt" only an NMI will wake you up. With spurious > wakeups, it's pretty much guaranteed that you will break such "cli;hlt" > sequences.
The architecture mandates some things that *must* wake you from a WFI, but it also allows wakeups for other reasons not listed, or for no reason at all. It's perfectly valid to implement WFI as a NOP (though it would not be very good for power efficiency, obviously). Guests which don't surround WFI with a "check whether we should just go back to WFI" loop are buggy. thanks -- PMM -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
