Re: [PATCH] KVM: riscv: selftests: Add SBI base extension test

[Andrew Jones]

On Mon, Apr 01, 2024 at 04:20:18PM +0800, Haibo Xu wrote:
> This is the first patch to enable the base extension selftest
> for the SBI implementation in KVM. Test for other extensions
> will be added later.

I'm not sure we want SBI tests in KVM selftests since we already
plan to add them to kvm-unit-tests, where they can be used to
test both KVM's SBI implementation and M-mode firmware implementations.
If we also have them here, then we'll end up duplicating that effort.

I do like the approach of only checking for an error, rather than
also for a value, for these ID getters. In kvm-unit-tests we're
currently requiring that the expected value be passed in, otherwise
the whole test is skipped. We could fallback to only checking for
an error instead, as is done here.

Thanks,
drew

> 
> Signed-off-by: Haibo Xu <haibo1.xu@xxxxxxxxx>
> ---
>  tools/testing/selftests/kvm/Makefile          |  1 +
>  .../selftests/kvm/include/riscv/processor.h   |  8 +-
>  tools/testing/selftests/kvm/riscv/sbi_test.c  | 95 +++++++++++++++++++
>  3 files changed, 103 insertions(+), 1 deletion(-)
>  create mode 100644 tools/testing/selftests/kvm/riscv/sbi_test.c
> 
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index 741c7dc16afc..a6acbbcad757 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -189,6 +189,7 @@ TEST_GEN_PROGS_s390x += rseq_test
>  TEST_GEN_PROGS_s390x += set_memory_region_test
>  TEST_GEN_PROGS_s390x += kvm_binary_stats_test
>  
> +TEST_GEN_PROGS_riscv += riscv/sbi_test
>  TEST_GEN_PROGS_riscv += arch_timer
>  TEST_GEN_PROGS_riscv += demand_paging_test
>  TEST_GEN_PROGS_riscv += dirty_log_test
> diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h
> index ce473fe251dd..df530ac751c4 100644
> --- a/tools/testing/selftests/kvm/include/riscv/processor.h
> +++ b/tools/testing/selftests/kvm/include/riscv/processor.h
> @@ -178,7 +178,13 @@ enum sbi_ext_id {
>  };
>  
>  enum sbi_ext_base_fid {
> -	SBI_EXT_BASE_PROBE_EXT = 3,
> +	SBI_EXT_BASE_GET_SPEC_VERSION = 0,
> +	SBI_EXT_BASE_GET_IMP_ID,
> +	SBI_EXT_BASE_GET_IMP_VERSION,
> +	SBI_EXT_BASE_PROBE_EXT,
> +	SBI_EXT_BASE_GET_MVENDORID,
> +	SBI_EXT_BASE_GET_MARCHID,
> +	SBI_EXT_BASE_GET_MIMPID,
>  };
>  
>  struct sbiret {
> diff --git a/tools/testing/selftests/kvm/riscv/sbi_test.c b/tools/testing/selftests/kvm/riscv/sbi_test.c
> new file mode 100644
> index 000000000000..b9378546e3b6
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/riscv/sbi_test.c
> @@ -0,0 +1,95 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * sbi_test - SBI API test for KVM's SBI implementation.
> + *
> + * Copyright (c) 2024 Intel Corporation
> + *
> + * Test cover the following SBI extentions:
> + *  - Base: All functions in this extension should be supported
> + */
> +
> +#include "kvm_util.h"
> +#include "processor.h"
> +#include "test_util.h"
> +
> +/*
> + * Test that all functions in the base extension must be supported
> + */
> +static void base_ext_guest_code(void)
> +{
> +	struct sbiret ret;
> +
> +	/*
> +	 * Since the base extension was introduced in SBI Spec v0.2,
> +	 * assert if the implemented SBI version is below 0.2.
> +	 */
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error && ret.value >= 2, "Get Spec Version Error: ret.error=%ld, "
> +			"ret.value=%ld\n", ret.error, ret.value);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_ID, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error && ret.value == 3, "Get Imp ID Error: ret.error=%ld, "
> +			"ret.value=%ld\n",
> +			ret.error, ret.value);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error, "Get Imp Version Error: ret.error=%ld\n", ret.error);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, SBI_EXT_BASE,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error && ret.value == 1, "Probe ext Error: ret.error=%ld, "
> +			"ret.value=%ld\n",
> +			ret.error, ret.value);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MVENDORID, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error, "Get Machine Vendor ID Error: ret.error=%ld\n", ret.error);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MARCHID, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error, "Get Machine Arch ID Error: ret.error=%ld\n", ret.error);
> +
> +	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MIMPID, 0,
> +			0, 0, 0, 0, 0);
> +	__GUEST_ASSERT(!ret.error, "Get Machine Imp ID Error: ret.error=%ld\n", ret.error);
> +
> +	GUEST_DONE();
> +}
> +
> +static void sbi_base_ext_test(void)
> +{
> +	struct kvm_vm *vm;
> +	struct kvm_vcpu *vcpu;
> +	struct ucall uc;
> +
> +	vm = vm_create_with_one_vcpu(&vcpu, base_ext_guest_code);
> +	while (1) {
> +		vcpu_run(vcpu);
> +		TEST_ASSERT(vcpu->run->exit_reason == UCALL_EXIT_REASON,
> +			    "Unexpected exit reason: %u (%s),",
> +			    vcpu->run->exit_reason, exit_reason_str(vcpu->run->exit_reason));
> +
> +		switch (get_ucall(vcpu, &uc)) {
> +		case UCALL_DONE:
> +			goto done;
> +		case UCALL_ABORT:
> +			fprintf(stderr, "Guest assert failed!\n");
> +			REPORT_GUEST_ASSERT(uc);
> +		default:
> +			TEST_FAIL("Unexpected ucall %lu", uc.cmd);
> +		}
> +	}
> +
> +done:
> +	kvm_vm_free(vm);
> +}
> +
> +int main(void)
> +{
> +	sbi_base_ext_test();
> +
> +	return 0;
> +}
> -- 
> 2.34.1
>