KVM: arm64: selftest: Expand external_aborts test to look for TTW levels

Add a basic test corrupting a level-2 table entry to check that
the resulting abort is a SEA on a PTW at level-3.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/tools/testing/selftests/kvm/arm64/external_aborts.c b/tools/testing/selftests/kvm/arm64/external_aborts.c
index 062bf84cced1381c47920a0adc6d3693efae5611..592b26ded779a8576651d5d04cb4b1fda11b1315 100644 (file)
--- a/tools/testing/selftests/kvm/arm64/external_aborts.c
+++ b/tools/testing/selftests/kvm/arm64/external_aborts.c
@@ -250,6 +250,47 @@ static void test_serror(void)
        kvm_vm_free(vm);
 }
 
+static void expect_sea_s1ptw_handler(struct ex_regs *regs)
+{
+       u64 esr = read_sysreg(esr_el1);
+
+       GUEST_ASSERT_EQ(regs->pc, expected_abort_pc);
+       GUEST_ASSERT_EQ(ESR_ELx_EC(esr), ESR_ELx_EC_DABT_CUR);
+       GUEST_ASSERT_EQ((esr & ESR_ELx_FSC), ESR_ELx_FSC_SEA_TTW(3));
+
+       GUEST_DONE();
+}
+
+static noinline void test_s1ptw_abort_guest(void)
+{
+       extern char test_s1ptw_abort_insn;
+
+       WRITE_ONCE(expected_abort_pc, (u64)&test_s1ptw_abort_insn);
+
+       asm volatile("test_s1ptw_abort_insn:\n\t"
+                    "ldr x0, [%0]\n\t"
+                    : : "r" (MMIO_ADDR) : "x0", "memory");
+
+       GUEST_FAIL("Load on S1PTW abort should not retire");
+}
+
+static void test_s1ptw_abort(void)
+{
+       struct kvm_vcpu *vcpu;
+       u64 *ptep, bad_pa;
+       struct kvm_vm *vm = vm_create_with_dabt_handler(&vcpu, test_s1ptw_abort_guest,
+                                                       expect_sea_s1ptw_handler);
+
+       ptep = virt_get_pte_hva_at_level(vm, MMIO_ADDR, 2);
+       bad_pa = BIT(vm->pa_bits) - vm->page_size;
+
+       *ptep &= ~GENMASK(47, 12);
+       *ptep |= bad_pa;
+
+       vcpu_run_expect_done(vcpu);
+       kvm_vm_free(vm);
+}
+
 static void test_serror_emulated_guest(void)
 {
        GUEST_ASSERT(!(read_sysreg(isr_el1) & ISR_EL1_A));
@@ -327,4 +368,5 @@ int main(void)
        test_serror_masked();
        test_serror_emulated();
        test_mmio_ease();
+       test_s1ptw_abort();
 }

diff --git a/tools/testing/selftests/kvm/include/arm64/processor.h b/tools/testing/selftests/kvm/include/arm64/processor.h
index 255fed769a8a54ece6876e2106d42f9184dafbc4..e3e916b1d9c4ede6be2469cb2a52a653bbaed3fc 100644 (file)
--- a/tools/testing/selftests/kvm/include/arm64/processor.h
+++ b/tools/testing/selftests/kvm/include/arm64/processor.h
@@ -175,6 +175,7 @@ void vm_install_exception_handler(struct kvm_vm *vm,
 void vm_install_sync_handler(struct kvm_vm *vm,
                int vector, int ec, handler_fn handler);
 
+uint64_t *virt_get_pte_hva_at_level(struct kvm_vm *vm, vm_vaddr_t gva, int level);
 uint64_t *virt_get_pte_hva(struct kvm_vm *vm, vm_vaddr_t gva);
 
 static inline void cpu_relax(void)

diff --git a/tools/testing/selftests/kvm/lib/arm64/processor.c b/tools/testing/selftests/kvm/lib/arm64/processor.c
index eb115123d74118035b6f09ecc52a4b51eca9be51..bd7480a93f96329992431256dbb50023dc6bf195 100644 (file)
--- a/tools/testing/selftests/kvm/lib/arm64/processor.c
+++ b/tools/testing/selftests/kvm/lib/arm64/processor.c
@@ -185,7 +185,7 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
        _virt_pg_map(vm, vaddr, paddr, attr_idx);
 }
 
-uint64_t *virt_get_pte_hva(struct kvm_vm *vm, vm_vaddr_t gva)
+uint64_t *virt_get_pte_hva_at_level(struct kvm_vm *vm, vm_vaddr_t gva, int level)
 {
        uint64_t *ptep;
 
@@ -195,17 +195,23 @@ uint64_t *virt_get_pte_hva(struct kvm_vm *vm, vm_vaddr_t gva)
        ptep = addr_gpa2hva(vm, vm->pgd) + pgd_index(vm, gva) * 8;
        if (!ptep)
                goto unmapped_gva;
+       if (level == 0)
+               return ptep;
 
        switch (vm->pgtable_levels) {
        case 4:
                ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pud_index(vm, gva) * 8;
                if (!ptep)
                        goto unmapped_gva;
+               if (level == 1)
+                       break;
                /* fall through */
        case 3:
                ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pmd_index(vm, gva) * 8;
                if (!ptep)
                        goto unmapped_gva;
+               if (level == 2)
+                       break;
                /* fall through */
        case 2:
                ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pte_index(vm, gva) * 8;
@@ -223,6 +229,11 @@ unmapped_gva:
        exit(EXIT_FAILURE);
 }
 
+uint64_t *virt_get_pte_hva(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+       return virt_get_pte_hva_at_level(vm, gva, 3);
+}
+
 vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
 {
        uint64_t *ptep = virt_get_pte_hva(vm, gva);