From: Yosry Ahmed Add the necessary infrastructure to support setting up nested NPTs and creating nested NPT mappings. There is some redundancy between nested_npt_create_pte() and nested_ept_create_pte(), especially that we access the same fields in both. An alternative is to have a single function in nested_map.c, and use macros to cast an obaque PTE pointer to the correct type (EPT entry vs NPT entry). Add a check in kvm_cpu_has_ept() to return false on AMD CPUs without attempting to read VMX-specific MSRs, since now it can be called on AMD CPUs. Generalize the code in vmx_dirty_log_test.c by adding SVM-specific L1 code, doing some renaming (e.g. EPT -> TDP), and having setup code for both SVM and VMX in test_dirty_log(). Having multiple points to check for SVM vs VMX is not ideal, but the alternatives either include a lot of redundancy or a lot of abstracting functions that will make the test logic harder to follow. Signed-off-by: Yosry Ahmed --- tools/testing/selftests/kvm/Makefile.kvm | 2 +- .../selftests/kvm/include/x86/svm_util.h | 13 +++ tools/testing/selftests/kvm/lib/x86/svm.c | 70 ++++++++++++++ tools/testing/selftests/kvm/lib/x86/vmx.c | 3 + ...rty_log_test.c => nested_dirty_log_test.c} | 94 ++++++++++++++----- 5 files changed, 155 insertions(+), 27 deletions(-) rename tools/testing/selftests/kvm/x86/{vmx_dirty_log_test.c => nested_dirty_log_test.c} (62%) diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm index 9547d7263e236..acedbf726f493 100644 --- a/tools/testing/selftests/kvm/Makefile.kvm +++ b/tools/testing/selftests/kvm/Makefile.kvm @@ -113,7 +113,7 @@ TEST_GEN_PROGS_x86 += x86/userspace_io_test TEST_GEN_PROGS_x86 += x86/userspace_msr_exit_test TEST_GEN_PROGS_x86 += x86/vmx_apic_access_test TEST_GEN_PROGS_x86 += x86/close_while_nested_test -TEST_GEN_PROGS_x86 += x86/vmx_dirty_log_test +TEST_GEN_PROGS_x86 += x86/nested_dirty_log_test TEST_GEN_PROGS_x86 += x86/vmx_exception_with_invalid_guest_state TEST_GEN_PROGS_x86 += x86/vmx_msrs_test TEST_GEN_PROGS_x86 += x86/vmx_invalid_nested_guest_state diff --git a/tools/testing/selftests/kvm/include/x86/svm_util.h b/tools/testing/selftests/kvm/include/x86/svm_util.h index b74c6dcddcbd6..84b79113b5433 100644 --- a/tools/testing/selftests/kvm/include/x86/svm_util.h +++ b/tools/testing/selftests/kvm/include/x86/svm_util.h @@ -27,6 +27,11 @@ struct svm_test_data { void *msr; /* gva */ void *msr_hva; uint64_t msr_gpa; + + /* NPT */ + void *ncr3; /* gva */ + void *ncr3_hva; + uint64_t ncr3_gpa; }; static inline void vmmcall(void) @@ -57,6 +62,14 @@ struct svm_test_data *vcpu_alloc_svm(struct kvm_vm *vm, vm_vaddr_t *p_svm_gva); void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_rsp); void run_guest(struct vmcb *vmcb, uint64_t vmcb_gpa); +bool nested_npt_create_pte(struct kvm_vm *vm, + uint64_t *pte, + uint64_t paddr, + uint64_t *address, + bool *leaf); +bool kvm_cpu_has_npt(void); +void prepare_npt(struct svm_test_data *svm, struct kvm_vm *vm); + int open_sev_dev_path_or_exit(void); #endif /* SELFTEST_KVM_SVM_UTILS_H */ diff --git a/tools/testing/selftests/kvm/lib/x86/svm.c b/tools/testing/selftests/kvm/lib/x86/svm.c index d239c20973918..9524abf7e779a 100644 --- a/tools/testing/selftests/kvm/lib/x86/svm.c +++ b/tools/testing/selftests/kvm/lib/x86/svm.c @@ -16,6 +16,23 @@ struct gpr64_regs guest_regs; u64 rflags; +struct nptPageTableEntry { + uint64_t present:1; + uint64_t writable:1; + uint64_t user:1; + uint64_t pwt:1; + uint64_t pcd:1; + uint64_t accessed:1; + uint64_t dirty:1; + uint64_t page_size:1; + uint64_t global:1; + uint64_t avail1:3; + uint64_t address:40; + uint64_t avail2:11; + uint64_t nx:1; +}; +static_assert(sizeof(struct nptPageTableEntry) == sizeof(uint64_t)); + /* Allocate memory regions for nested SVM tests. * * Input Args: @@ -59,6 +76,54 @@ static void vmcb_set_seg(struct vmcb_seg *seg, u16 selector, seg->base = base; } +bool nested_npt_create_pte(struct kvm_vm *vm, + uint64_t *pte, + uint64_t paddr, + uint64_t *address, + bool *leaf) +{ + struct nptPageTableEntry *npte = (struct nptPageTableEntry *)pte; + + if (npte->present) { + *leaf = npte->page_size; + *address = npte->address; + return false; + } + + npte->present = true; + npte->writable = true; + npte->page_size = *leaf; + + if (*leaf) + npte->address = paddr >> vm->page_shift; + else + npte->address = vm_alloc_page_table(vm) >> vm->page_shift; + + *address = npte->address; + + /* + * For now mark these as accessed and dirty because the only + * testcase we have needs that. Can be reconsidered later. + */ + npte->accessed = *leaf; + npte->dirty = *leaf; + return true; +} + +bool kvm_cpu_has_npt(void) +{ + return kvm_cpu_has(X86_FEATURE_NPT); +} + +void prepare_npt(struct svm_test_data *svm, struct kvm_vm *vm) +{ + TEST_ASSERT(kvm_cpu_has_npt(), "KVM doesn't support nested NPT"); + + svm->ncr3 = (void *)vm_vaddr_alloc_page(vm); + svm->ncr3_hva = addr_gva2hva(vm, (uintptr_t)svm->ncr3); + svm->ncr3_gpa = addr_gva2gpa(vm, (uintptr_t)svm->ncr3); +} + void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_rsp) { struct vmcb *vmcb = svm->vmcb; @@ -102,6 +167,11 @@ void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_r vmcb->save.rip = (u64)guest_rip; vmcb->save.rsp = (u64)guest_rsp; guest_regs.rdi = (u64)svm; + + if (svm->ncr3_gpa) { + ctrl->nested_ctl |= SVM_NESTED_CTL_NP_ENABLE; + ctrl->nested_cr3 = svm->ncr3_gpa; + } } /* diff --git a/tools/testing/selftests/kvm/lib/x86/vmx.c b/tools/testing/selftests/kvm/lib/x86/vmx.c index 24345213fcd04..0ced959184cd9 100644 --- a/tools/testing/selftests/kvm/lib/x86/vmx.c +++ b/tools/testing/selftests/kvm/lib/x86/vmx.c @@ -405,6 +405,9 @@ bool kvm_cpu_has_ept(void) { uint64_t ctrl; + if (!kvm_cpu_has(X86_FEATURE_VMX)) + return false; + ctrl = kvm_get_feature_msr(MSR_IA32_VMX_TRUE_PROCBASED_CTLS) >> 32; if (!(ctrl & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS)) return false; diff --git a/tools/testing/selftests/kvm/x86/vmx_dirty_log_test.c b/tools/testing/selftests/kvm/x86/nested_dirty_log_test.c similarity index 62% rename from tools/testing/selftests/kvm/x86/vmx_dirty_log_test.c rename to tools/testing/selftests/kvm/x86/nested_dirty_log_test.c index db88a1e5e9d0c..56f741ddce944 100644 --- a/tools/testing/selftests/kvm/x86/vmx_dirty_log_test.c +++ b/tools/testing/selftests/kvm/x86/nested_dirty_log_test.c @@ -13,6 +13,7 @@ #include "kvm_util.h" #include "nested_map.h" #include "processor.h" +#include "svm_util.h" #include "vmx.h" /* The memory slot index to track dirty pages */ @@ -26,6 +27,8 @@ #define NESTED_TEST_MEM1 0xc0001000 #define NESTED_TEST_MEM2 0xc0002000 +#define L2_GUEST_STACK_SIZE 64 + static void l2_guest_code(u64 *a, u64 *b) { READ_ONCE(*a); @@ -43,20 +46,19 @@ static void l2_guest_code(u64 *a, u64 *b) vmcall(); } -static void l2_guest_code_ept_enabled(void) +static void l2_guest_code_tdp_enabled(void) { l2_guest_code((u64 *)NESTED_TEST_MEM1, (u64 *)NESTED_TEST_MEM2); } -static void l2_guest_code_ept_disabled(void) +static void l2_guest_code_tdp_disabled(void) { - /* Access the same L1 GPAs as l2_guest_code_ept_enabled() */ + /* Access the same L1 GPAs as l2_guest_code_tdp_enabled() */ l2_guest_code((u64 *)GUEST_TEST_MEM, (u64 *)GUEST_TEST_MEM); } -void l1_guest_code(struct vmx_pages *vmx) +void l1_vmx_code(struct vmx_pages *vmx) { -#define L2_GUEST_STACK_SIZE 64 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; void *l2_rip; @@ -65,9 +67,9 @@ void l1_guest_code(struct vmx_pages *vmx) GUEST_ASSERT(load_vmcs(vmx)); if (vmx->eptp_gpa) - l2_rip = l2_guest_code_ept_enabled; + l2_rip = l2_guest_code_tdp_enabled; else - l2_rip = l2_guest_code_ept_disabled; + l2_rip = l2_guest_code_tdp_disabled; prepare_vmcs(vmx, l2_rip, &l2_guest_stack[L2_GUEST_STACK_SIZE]); @@ -78,10 +80,38 @@ void l1_guest_code(struct vmx_pages *vmx) GUEST_DONE(); } -static void test_vmx_dirty_log(bool enable_ept) +static void l1_svm_code(struct svm_test_data *svm) +{ + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + void *l2_rip; + + if (svm->ncr3_gpa) + l2_rip = l2_guest_code_tdp_enabled; + else + l2_rip = l2_guest_code_tdp_disabled; + + generic_svm_setup(svm, l2_rip, &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + GUEST_SYNC(false); + run_guest(svm->vmcb, svm->vmcb_gpa); + GUEST_SYNC(false); + GUEST_ASSERT(svm->vmcb->control.exit_code == SVM_EXIT_VMMCALL); + GUEST_DONE(); +} + +static void l1_guest_code(void *data) +{ + if (this_cpu_has(X86_FEATURE_VMX)) + l1_vmx_code(data); + else + l1_svm_code(data); +} + +static void test_dirty_log(bool enable_tdp) { - vm_vaddr_t vmx_pages_gva = 0; - struct vmx_pages *vmx; + struct svm_test_data *svm = NULL; + struct vmx_pages *vmx = NULL; + vm_vaddr_t nested_gva = 0; unsigned long *bmap; uint64_t *host_test_mem; @@ -90,12 +120,16 @@ static void test_vmx_dirty_log(bool enable_ept) struct ucall uc; bool done = false; - pr_info("Nested EPT: %s\n", enable_ept ? "enabled" : "disabled"); + pr_info("Nested TDP: %s\n", enable_tdp ? "enabled" : "disabled"); /* Create VM */ vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code); - vmx = vcpu_alloc_vmx(vm, &vmx_pages_gva); - vcpu_args_set(vcpu, 1, vmx_pages_gva); + if (kvm_cpu_has(X86_FEATURE_VMX)) + vmx = vcpu_alloc_vmx(vm, &nested_gva); + else + svm = vcpu_alloc_svm(vm, &nested_gva); + + vcpu_args_set(vcpu, 1, nested_gva); /* Add an extra memory slot for testing dirty logging */ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, @@ -114,17 +148,25 @@ static void test_vmx_dirty_log(bool enable_ept) * ... pages in the L2 GPA range [0xc0001000, 0xc0003000) will map to * 0xc0000000. * - * Note that prepare_eptp should be called only L1's GPA map is done, - * meaning after the last call to virt_map. + * Note that prepare_eptp()/prepare_npt() should be called only when + * L1's GPA map is done, meaning after the last call to virt_map. * - * When EPT is disabled, the L2 guest code will still access the same L1 - * GPAs as the EPT enabled case. + * When TDP is disabled, the L2 guest code will still access the same L1 + * GPAs as the TDP enabled case. */ - if (enable_ept) { - prepare_eptp(vmx, vm, 0); - nested_map_memslot(vmx->eptp_hva, vm, 0); - nested_map(vmx->eptp_hva, vm, NESTED_TEST_MEM1, GUEST_TEST_MEM, 4096); - nested_map(vmx->eptp_hva, vm, NESTED_TEST_MEM2, GUEST_TEST_MEM, 4096); + if (enable_tdp) { + void *root_hva; + + if (kvm_cpu_has(X86_FEATURE_VMX)) { + prepare_eptp(vmx, vm, 0); + root_hva = vmx->eptp_hva; + } else { + prepare_npt(svm, vm); + root_hva = svm->ncr3_hva; + } + nested_map_memslot(root_hva, vm, 0); + nested_map(root_hva, vm, NESTED_TEST_MEM1, GUEST_TEST_MEM, 4096); + nested_map(root_hva, vm, NESTED_TEST_MEM2, GUEST_TEST_MEM, 4096); } bmap = bitmap_zalloc(TEST_MEM_PAGES); @@ -169,12 +211,12 @@ static void test_vmx_dirty_log(bool enable_ept) int main(int argc, char *argv[]) { - TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX)); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX) || kvm_cpu_has(X86_FEATURE_SVM)); - test_vmx_dirty_log(/*enable_ept=*/false); + test_dirty_log(/*enable_tdp=*/false); - if (kvm_cpu_has_ept()) - test_vmx_dirty_log(/*enable_ept=*/true); + if (kvm_cpu_has_ept() || kvm_cpu_has_npt()) + test_dirty_log(/*enable_tdp=*/true); return 0; } -- 2.51.0.618.g983fd99d29-goog