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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 2F11620007 X-Stat-Signature: mdrsf9jikom83ta745uo3p5gufogyqt6 X-Rspam-User: X-HE-Tag: 1768398487-892829 X-HE-Meta: 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 D6ekbWp4 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Patrick Roy =0A= =0A= Add a selftest that loads itself into guest_memfd (via=0A= GUEST_MEMFD_FLAG_MMAP) and triggers an MMIO exit when executed. This=0A= exercises x86 MMIO emulation code inside KVM for guest_memfd-backed=0A= memslots where the guest_memfd folios are direct map removed.=0A= Particularly, it validates that x86 MMIO emulation code (guest page=0A= table walks + instruction fetch) correctly accesses gmem through the VMA=0A= that's been reflected into the memslot's userspace_addr field (instead=0A= of trying to do direct map accesses).=0A= =0A= Signed-off-by: Patrick Roy =0A= Signed-off-by: Nikita Kalyazin =0A= ---=0A= .../selftests/kvm/set_memory_region_test.c | 52 +++++++++++++++++--=0A= 1 file changed, 48 insertions(+), 4 deletions(-)=0A= =0A= diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/t= esting/selftests/kvm/set_memory_region_test.c=0A= index 7fe427ff9b38..6c57fb036b20 100644=0A= --- a/tools/testing/selftests/kvm/set_memory_region_test.c=0A= +++ b/tools/testing/selftests/kvm/set_memory_region_test.c=0A= @@ -602,6 +602,41 @@ static void test_mmio_during_vectoring(void)=0A= =0A= kvm_vm_free(vm);=0A= }=0A= +=0A= +static void guest_code_trigger_mmio(void)=0A= +{=0A= + /*=0A= + * Read some GPA that is not backed by a memslot. KVM consider this=0A= + * as MMIO and tell userspace to emulate the read.=0A= + */=0A= + READ_ONCE(*((uint64_t *)MEM_REGION_GPA));=0A= +=0A= + GUEST_DONE();=0A= +}=0A= +=0A= +static void test_guest_memfd_mmio(void)=0A= +{=0A= + struct kvm_vm *vm;=0A= + struct kvm_vcpu *vcpu;=0A= + struct vm_shape shape =3D {=0A= + .mode =3D VM_MODE_DEFAULT,=0A= + .src_type =3D VM_MEM_SRC_GUEST_MEMFD_NO_DIRECT_MAP,=0A= + };=0A= + pthread_t vcpu_thread;=0A= +=0A= + pr_info("Testing MMIO emulation for instructions in gmem\n");=0A= +=0A= + vm =3D __vm_create_shape_with_one_vcpu(shape, &vcpu, 0, guest_code_trigge= r_mmio);=0A= +=0A= + virt_map(vm, MEM_REGION_GPA, MEM_REGION_GPA, 1);=0A= +=0A= + pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);=0A= +=0A= + /* If the MMIO read was successfully emulated, the vcpu thread will exit = */=0A= + pthread_join(vcpu_thread, NULL);=0A= +=0A= + kvm_vm_free(vm);=0A= +}=0A= #endif=0A= =0A= int main(int argc, char *argv[])=0A= @@ -625,10 +660,19 @@ int main(int argc, char *argv[])=0A= test_add_max_memory_regions();=0A= =0A= #ifdef __x86_64__=0A= - if (kvm_has_cap(KVM_CAP_GUEST_MEMFD) &&=0A= - (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM))) {= =0A= - test_add_private_memory_region();=0A= - test_add_overlapping_private_memory_regions();=0A= + if (kvm_has_cap(KVM_CAP_GUEST_MEMFD)) {=0A= + uint64_t valid_flags =3D kvm_check_cap(KVM_CAP_GUEST_MEMFD_FLAGS);=0A= +=0A= + if (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM)) {=0A= + test_add_private_memory_region();=0A= + test_add_overlapping_private_memory_regions();=0A= + }=0A= +=0A= + if ((valid_flags & GUEST_MEMFD_FLAG_MMAP)=0A= + && (valid_flags & GUEST_MEMFD_FLAG_NO_DIRECT_MAP))=0A= + test_guest_memfd_mmio();=0A= + else=0A= + pr_info("Skipping tests requiring GUEST_MEMFD_FLAG_MMAP | GUEST_MEMFD_F= LAG_NO_DIRECT_MAP");=0A= } else {=0A= pr_info("Skipping tests for KVM_MEM_GUEST_MEMFD memory regions\n");=0A= }=0A= -- =0A= 2.50.1=0A= =0A=