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Re: [Xen-ia64-devel][Patch]Add two PAL calls which fix SMPwindowsinstallation crashing bug
Tristan Gingold writes:
> > In 10, I don't understand why the special SAL_XEN_SAL_RETURN is
> > necessary instead of PAL_HALT. The difference is test_and_set_bit() or
> > set_bit(). I think a vcpu with VCPU_down state never be at this point.
> > Besides calling vcpu_sleep_no_sync() with VCPU_down state seems to be
> > harmless.
> Humm, to be discussed:
> Although the implementation may be almost the same, I think the semantic is
> After SAL_XEN_SAL_RETURN, the processor can be awaken only by a rendez-vous.
> Its state is reset.
> After PAL_HALT, the processor can be awaken by an IPI. Its state is
I see. For example, preserving a vcpu context is unnecessary after
SAL_XEN_SAL_RETURN for save/restore of a domain.
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