On Tue, Oct 21, 2025 at 03:34:22PM -0700, Jim Mattson wrote: > On Wed, Oct 15, 2025 at 2:23 PM Yosry Ahmed <[email protected]> wrote: > > > > On Wed, Sep 17, 2025 at 02:48:39PM -0700, Jim Mattson wrote: > > > Add a new VM mode, VM_MODE_PXXV57_4K, to support tests that require > > > 5-level paging on x86. This mode sets up a 57-bit virtual address > > > space and sets CR4.LA57 in the guest. > > > > > > Signed-off-by: Jim Mattson <[email protected]> > > > --- > > > .../testing/selftests/kvm/include/kvm_util.h | 1 + > > > tools/testing/selftests/kvm/lib/kvm_util.c | 21 +++++++++++++++++ > > > .../testing/selftests/kvm/lib/x86/processor.c | 23 ++++++++++++------- > > > tools/testing/selftests/kvm/lib/x86/vmx.c | 7 +++--- > > > 4 files changed, 41 insertions(+), 11 deletions(-) > > > > > > ... > > > diff --git a/tools/testing/selftests/kvm/lib/x86/vmx.c > > > b/tools/testing/selftests/kvm/lib/x86/vmx.c > > > index d4d1208dd023..1b6d4a007798 100644 > > > --- a/tools/testing/selftests/kvm/lib/x86/vmx.c > > > +++ b/tools/testing/selftests/kvm/lib/x86/vmx.c > > > @@ -401,11 +401,12 @@ void __nested_pg_map(struct vmx_pages *vmx, struct > > > kvm_vm *vm, > > > struct eptPageTableEntry *pt = vmx->eptp_hva, *pte; > > > uint16_t index; > > > > > > - TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use " > > > - "unknown or unsupported guest mode, mode: 0x%x", > > > vm->mode); > > > + TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K || > > > + vm->mode == VM_MODE_PXXV57_4K, > > > + "Unknown or unsupported guest mode: 0x%x", vm->mode); > > > > > > TEST_ASSERT((nested_paddr >> 48) == 0, > > > - "Nested physical address 0x%lx requires 5-level paging", > > > + "Nested physical address 0x%lx is > 48-bits and > > > requires 5-level EPT", > > > > Shouldn't this assertion be updated now? We technically support 5-level > > EPT so it should only fire if the mode is VM_MODE_PXXV48_4K. Maybe we > > should use vm->va_bits? > > I did update the assertion! :) > > init_vmcs_control_fields() hardcodes a page-walk-length of 4 in the > EPTP, and the loop in __nested_pg_map() counts down from > PG_LEVEL_512G. There is no support for 5-level EPT here.
__nested_pg_map() will be gone with the series [1] moving nested mappings to use __virt_pg_map(), and with your series the latter does support 5-level EPTs. init_vmcs_control_fields() still hardcodes a page-walk-length of 4 tho. I actually just realized, my series will already drop these assertions and rely on the ones in __virt_pg_map(), which do use vm->page_shift, so the assertion won't fire if init_vmcs_control_fields() starts using 5-level EPTs. TL;DR nothing to do here. [1]https://lore.kernel.org/kvm/[email protected]/ > > > > > > nested_paddr); > > > TEST_ASSERT((nested_paddr % page_size) == 0, > > > "Nested physical address not on page boundary,\n" > > > -- > > > 2.51.0.470.ga7dc726c21-goog > > > > >
