This selftest simply starts an L1, which starts its own guest (L2). L2 runs without stage-1 and 2 translations, it calls an HVC to jump back to L1.
Signed-off-by: Wei-Lin Chang <[email protected]> --- tools/testing/selftests/kvm/Makefile.kvm | 1 + .../selftests/kvm/arm64/hello_nested.c | 104 ++++++++++++++++++ 2 files changed, 105 insertions(+) create mode 100644 tools/testing/selftests/kvm/arm64/hello_nested.c diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm index 3dc3e39f7025..e8c108e0c487 100644 --- a/tools/testing/selftests/kvm/Makefile.kvm +++ b/tools/testing/selftests/kvm/Makefile.kvm @@ -168,6 +168,7 @@ TEST_GEN_PROGS_arm64 += arm64/arch_timer_edge_cases TEST_GEN_PROGS_arm64 += arm64/at TEST_GEN_PROGS_arm64 += arm64/debug-exceptions TEST_GEN_PROGS_arm64 += arm64/hello_el2 +TEST_GEN_PROGS_arm64 += arm64/hello_nested TEST_GEN_PROGS_arm64 += arm64/host_sve TEST_GEN_PROGS_arm64 += arm64/hypercalls TEST_GEN_PROGS_arm64 += arm64/external_aborts diff --git a/tools/testing/selftests/kvm/arm64/hello_nested.c b/tools/testing/selftests/kvm/arm64/hello_nested.c new file mode 100644 index 000000000000..1cab56e4597b --- /dev/null +++ b/tools/testing/selftests/kvm/arm64/hello_nested.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * hello_nested - Go from vEL2 to EL1 then back + */ + +#include "nested.h" +#include "processor.h" +#include "test_util.h" +#include "ucall.h" + +#define XLATE2GPA (0xABCD) +#define L2STACKSZ (0x100) + +/* + * TPIDR_EL2 is used to store vcpu id, so save and restore it. + */ +static gpa_t ucall_translate_to_gpa(void *gva) +{ + gpa_t gpa; + u64 vcpu_id = read_sysreg(tpidr_el2); + + GUEST_SYNC2(XLATE2GPA, gva); + + /* get the result from userspace */ + gpa = read_sysreg(tpidr_el2); + + write_sysreg(vcpu_id, tpidr_el2); + + return gpa; +} + +static void l2_guest_code(void) +{ + do_hvc(); +} + +static void guest_code(void) +{ + struct vcpu vcpu; + struct hyp_data hyp_data; + int ret; + gpa_t l2_pc, l2_stack_top; + /* force 16-byte alignment for the stack pointer */ + u8 l2_stack[L2STACKSZ] __attribute__((aligned(16))); + + GUEST_ASSERT_EQ(get_current_el(), 2); + GUEST_PRINTF("vEL2 entry\n"); + + l2_pc = ucall_translate_to_gpa(l2_guest_code); + l2_stack_top = ucall_translate_to_gpa(&l2_stack[L2STACKSZ]); + + init_vcpu(&vcpu, l2_pc, l2_stack_top); + prepare_hyp(); + + ret = run_l2(&vcpu, &hyp_data); + GUEST_ASSERT_EQ(ret, ARM_EXCEPTION_TRAP); + GUEST_ASSERT_EQ(ESR_ELx_EC(read_sysreg(esr_el2)), ESR_ELx_EC_HVC64); + GUEST_DONE(); +} + +int main(void) +{ + struct kvm_vcpu_init init; + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + struct ucall uc; + gpa_t gpa; + + TEST_REQUIRE(kvm_check_cap(KVM_CAP_ARM_EL2)); + vm = vm_create(1); + + kvm_get_default_vcpu_target(vm, &init); + init.features[0] |= BIT(KVM_ARM_VCPU_HAS_EL2); + vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code); + kvm_arch_vm_finalize_vcpus(vm); + + while (true) { + vcpu_run(vcpu); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_SYNC: + if (uc.args[0] == XLATE2GPA) { + gpa = addr_gva2gpa(vm, (gva_t)uc.args[1]); + vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_TPIDR_EL2), gpa); + } + break; + case UCALL_PRINTF: + pr_info("%s", uc.buffer); + break; + case UCALL_DONE: + pr_info("DONE!\n"); + goto end; + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + fallthrough; + default: + TEST_FAIL("Unhandled ucall: %ld\n", uc.cmd); + } + } + +end: + kvm_vm_free(vm); + return 0; +} -- 2.43.0
