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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 9/9/24 23:03, Edgecombe, Rick P wrote: > KVM code tends to be less wrapped and a tdx_vm_destory would be a > oneline function. So I think it fits in other ways. Yes, no problem there. Sometimes one-line functions are ok (see ept_sync_global() case elsewhere in the series), sometimes they're overkill, especially if they wrap a function defined in the same file as the wrapper. >>> +        * which causes gmem invalidation to zap all spte. >>> +        * Population is only allowed after KVM_TDX_INIT_VM. >>> +        */ >> What does the second sentence ("Population ...")  meaning?  Why is it >> relevant here? >> > How about: > /* > * HKID is released after all private pages have been removed, > * and set before any might be populated. Warn if zapping is > * attempted when there can't be anything populated in the private > * EPT. > */ > > But actually, I wonder if we need to remove the KVM_BUG_ON(). I think if you did > a KVM_PRE_FAULT_MEMORY and then deleted the memslot you could hit it? I think all paths to handle_removed_pt() are safe: __tdp_mmu_zap_root tdp_mmu_zap_root kvm_tdp_mmu_zap_all kvm_arch_flush_shadow_all kvm_flush_shadow_all kvm_destroy_vm (*) kvm_mmu_notifier_release (*) kvm_tdp_mmu_zap_invalidated_roots kvm_mmu_zap_all_fast (**) kvm_tdp_mmu_zap_sp kvm_recover_nx_huge_pages (***) (*) only called at destroy time (**) only invalidates direct roots (***) shouldn't apply to TDX I hope? Paolo