On Wed, Oct 11 2023, Oliver Upton <oliver.upton@xxxxxxxxx> wrote:
> From: Jing Zhang <jingzhangos@xxxxxxxxxx>
>
> Add tests to verify setting ID registers from userspace is handled
> correctly by KVM. Also add a test case to use ioctl
> KVM_ARM_GET_REG_WRITABLE_MASKS to get writable masks.
>
> Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx>
> Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx>
> ---
> tools/testing/selftests/kvm/Makefile | 1 +
> .../selftests/kvm/aarch64/set_id_regs.c | 479 ++++++++++++++++++
> 2 files changed, 480 insertions(+)
> create mode 100644 tools/testing/selftests/kvm/aarch64/set_id_regs.c
(...)
> +static void test_user_set_reg(struct kvm_vcpu *vcpu, bool aarch64_only)
> +{
> + uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
> + struct reg_mask_range range = {
> + .addr = (__u64)masks,
> + };
> + int ret;
> +
> + /* KVM should return error when reserved field is not zero */
> + range.reserved[0] = 1;
> + ret = __vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
> + TEST_ASSERT(ret, "KVM doesn't check invalid parameters.");
I think the code should first check for
KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES -- newer kselftests are supposed
to be able to run on older kernels, and we should just skip all of this
if the API isn't there.
> +
> + /* Get writable masks for feature ID registers */
> + memset(range.reserved, 0, sizeof(range.reserved));
> + vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
