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

[Haibo Xu]

On Tue, Apr 2, 2024 at 10:12 PM Andrew Jones <ajones@xxxxxxxxxxxxxxxx> wrote:
>
> 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.
>

Thanks for the information, Andrew!

The SBI KVM selftest was planned last year when I talked with Anup about
KVM selftest support on RISC-V. Since the kvm-unit-tests has already covered
it, I'm fine to drop the support in KVM selftest.

Regards,
Haibo

> 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
> >