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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 5/11/26 17:06, Paolo Bonzini wrote: > PDPTRs are part of the CPU state. A bit unconventionally, they are > reached via vcpu->arch.walk_mmu instead of being stored in vcpu->arch > directly. That is nice in principle---it would allow TDP shadow paging > to have its own PDPTRs---but it is not necessary, because EPT has no > PDPTRs and NPT does not cache them. > > Since kvm_pdptr_read does not otherwise need the MMU, drop the pdptrs > from the MMU altogether. There is however a negative effect, in that > they are now not stored separately in root_mmu and nested_mmu for L1 > and L2 guests. This means that they are overwritten by nested VM entry > and exit, and need to be manually marked dirty. > > Note that page table PDPTRs are not affected, since they are stored > in pae_root. The vmx/nested.c and svm/nested.c changes here are untested and completely broken - I mentioned this in the cover letter but should have done it here too in case anyone reviews this. But there are some cleanup opportunities now that I looked at it more closely. Paolo