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Should the kernel > > > at least spit a warning, given that it would surely fail the device? > > > > No, just let break, the resulting failure has to be contained to the > > VM or the platform is broken.. > > > > The HV can't turn on ATS because we it can't know what invalidations > > to push so not much other choice. > > > > Taking about in theory - host can append a devtlb invalidation cmd > after iotlb invalidation (if vcmdq is not used)? It can't map an ASID to a BDF without shadowing all the STE and CD tables which we don't do for nesting. Jason