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Check if VMM has provided an activated >> topology configuration first as it is the prerequisite of REDUCE_VE and >> ENUM_TOPOLOGY, so move it to reduce_unnecessary_ve(). The function >> enable_cpu_topology_enumeration() was very little and can be >> integrated into reduce_unnecessary_ve(). > > Isn't this just working around VMM bugs? Shouldn't we just panic as > quickly as possible so the VMM config gets fixed rather than adding kludges? Now failed to virtualize these two cases will cause TD VM regression vs legacy VM. Do you mean the panic will just for the #VE caused by CPUID leaf 0x2? Or both (+ VMM not configure topology) will panic? Currently the most customer's complaints come from the CPUID leaf 0x2 not virtualization, and most of access come from user space. Is it appropriate for such behavior directly cause a guest kernel panic? Thanks, Zhiquan