Re: [PATCH v4 00/21] KVM: selftests: Add Nested NPT support

Sean Christopherson
2026-01-12T17:41:13Z

On Tue, 30 Dec 2025 15:01:29 -0800, Sean Christopherson wrote:
> Yosry's series to add support for nested NPT, and extends vmx_dirty_log_test
> and kvm_dirty_log_test (with -n, using memstress) to cover nested SVM.
>
> Note, I'm mildly concerned the last patch to extend nested_dirty_log_test to
> validate KVM's handling of READ faults could be flaky, e.g. maybe if someone
> is running the test under heavy memory pressure and the to-be-access page is
> swapped between the write-from-host and read-from-guest? But unless someone
> knows/shows it'll be flaky, I'm inclined to apply it and hope for the best.
>
> [...]

Applied everything except the last patch to kvm-x86 selftests. I'll post a new
version separately since we've had a lot of back-and-forth on that one.

Oh, and I fixed up the ncr3_gpa goof in "Add support for nested NPTs".

[01/21] KVM: selftests: Make __vm_get_page_table_entry() static
https://github.com/kvm-x86/linux/commit/69e81ed5e6a5
[02/21] KVM: selftests: Stop passing a memslot to nested_map_memslot()
https://github.com/kvm-x86/linux/commit/97dfbdfea405
[03/21] KVM: selftests: Rename nested TDP mapping functions
https://github.com/kvm-x86/linux/commit/60de423781ad
[04/21] KVM: selftests: Kill eptPageTablePointer
https://github.com/kvm-x86/linux/commit/b320c03d6857
[05/21] KVM: selftests: Stop setting A/D bits when creating EPT PTEs
https://github.com/kvm-x86/linux/commit/3cd5002807be
[06/21] KVM: selftests: Add "struct kvm_mmu" to track a given MMU instance
https://github.com/kvm-x86/linux/commit/9f073ac25b4c
[07/21] KVM: selftests: Plumb "struct kvm_mmu" into x86's MMU APIs
https://github.com/kvm-x86/linux/commit/11825209f549
[08/21] KVM: selftests: Add a "struct kvm_mmu_arch arch" member to kvm_mmu
https://github.com/kvm-x86/linux/commit/3d0e7595e810
[09/21] KVM: selftests: Move PTE bitmasks to kvm_mmu
https://github.com/kvm-x86/linux/commit/6dd70757213f
[10/21] KVM: selftests: Use a TDP MMU to share EPT page tables between vCPUs
https://github.com/kvm-x86/linux/commit/f00f519cebcd
[11/21] KVM: selftests: Stop passing VMX metadata to TDP mapping functions
https://github.com/kvm-x86/linux/commit/e40e72fec0de
[12/21] KVM: selftests: Add a stage-2 MMU instance to kvm_vm
https://github.com/kvm-x86/linux/commit/8296b16c0a2b
[13/21] KVM: selftests: Reuse virt mapping functions for nested EPTs
https://github.com/kvm-x86/linux/commit/508d1cc3ca0a
[14/21] KVM: selftests: Move TDP mapping functions outside of vmx.c
https://github.com/kvm-x86/linux/commit/07676c04bd75
[15/21] KVM: selftests: Allow kvm_cpu_has_ept() to be called on AMD CPUs
https://github.com/kvm-x86/linux/commit/9cb1944f6bf0
[16/21] KVM: selftests: Add support for nested NPTs
https://github.com/kvm-x86/linux/commit/753c0d5a507b
[17/21] KVM: selftests: Set the user bit on nested NPT PTEs
https://github.com/kvm-x86/linux/commit/251e4849a79b
[18/21] KVM: selftests: Extend vmx_dirty_log_test to cover SVM
https://github.com/kvm-x86/linux/commit/6794d916f87e
[19/21] KVM: selftests: Extend memstress to run on nested SVM
https://github.com/kvm-x86/linux/commit/59eef1a47b8c
[20/21] KVM: selftests: Rename vm_get_page_table_entry() to vm_get_pte()
https://github.com/kvm-x86/linux/commit/e353850499c7
[21/21] KVM: selftests: Test READ=>WRITE dirty logging behavior for shadow MMU
*** NOT APPLIED ***

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