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On startup, for some reason Windows 11 Hyper-V tries to set the MSR to >> the spec-defined initial value and since the vector is 0, it GP faults. >> To workaround this, treat the write as a no-op if the value is >> unchanged. >> >> Signed-off-by: Ross Lagerwall > > Acked-by: Jan Beulich > > I expect that despite the (valid) absence of a Fixes: tag this will want > backporting. It should be fine to backport, though in general I think backporting nested virt fixes at this point is not needed as there will be too many changes to go into the stable releases for it to reach a usable state. Ross