Re: [PATCH 2/2] KVM: arm64: selftests: Add tests for MMIO external abort injection

[Oliver Upton <oliver.upton@linux.dev>]

On Fri, Oct 18, 2024 at 07:47:57PM +0000, Oliver Upton wrote:
> Test that the plumbing exposed to userspace for injecting aborts in
> response to unexpected MMIO works as intended in two different flavors:
> 
>  - A 'normal' MMIO instruction (i.e. ESR_ELx.ISV=1)
> 
>  - An ISV=0 MMIO instruction with/without KVM_CAP_ARM_NISV_TO_USER
>    enabled
> 
> Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
> ---
>  tools/testing/selftests/kvm/Makefile          |   1 +
>  .../selftests/kvm/aarch64/mmio_abort.c        | 158 ++++++++++++++++++
>  2 files changed, 159 insertions(+)
>  create mode 100644 tools/testing/selftests/kvm/aarch64/mmio_abort.c
> 
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index 960cf6a77198..98957a99ead6 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -156,6 +156,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/aarch32_id_regs
>  TEST_GEN_PROGS_aarch64 += aarch64/arch_timer_edge_cases
>  TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
>  TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
> +TEST_GEN_PROGS_aarch64 += aarch64/mmio_abort
>  TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
>  TEST_GEN_PROGS_aarch64 += aarch64/psci_test
>  TEST_GEN_PROGS_aarch64 += aarch64/set_id_regs
> diff --git a/tools/testing/selftests/kvm/aarch64/mmio_abort.c b/tools/testing/selftests/kvm/aarch64/mmio_abort.c
> new file mode 100644
> index 000000000000..08c4afec1f28
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/aarch64/mmio_abort.c
> @@ -0,0 +1,158 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * mmio_abort - Tests for userspace MMIO abort injection
> + *
> + * Copyright (c) 2024 Google LLC
> + */
> +#include "processor.h"
> +#include "test_util.h"
> +
> +#define MMIO_ADDR	0x8000000ULL
> +
> +#define ESR_ELx_FSC_EXTABT	(0x10)
> +
> +static u64 expected_abort_pc;
> +
> +static void expect_sea_handler(struct ex_regs *regs)
> +{
> +	GUEST_ASSERT_EQ(regs->pc, expected_abort_pc);
> +	GUEST_ASSERT(read_sysreg(esr_el1) & ESR_ELx_FSC_EXTABT);
> +

This needs to extract and compare the entire FSC field, I'll fix it the
next time around.

-- 
Thanks,
Oliver