Re: [PATCH] selftests: KVM: Gracefully handle missing vCPU features
From: Andrew Jones <hidden>
Date: 2021-08-19 10:33:00
Also in:
kvmarm
On Wed, Aug 18, 2021 at 09:29:40PM +0000, Oliver Upton wrote:
quoted hunk ↗ jump to hunk
An error of ENOENT for the KVM_ARM_VCPU_INIT ioctl indicates that one of the requested feature flags is not supported by the kernel/hardware. Detect the case when KVM doesn't support the requested features and skip the test rather than failing it. Cc: Andrew Jones <redacted> Signed-off-by: Oliver Upton <redacted> --- Applies to 5.14-rc6. Tested by running all selftests on an Ampere Mt. Jade system. .../testing/selftests/kvm/lib/aarch64/processor.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c index 632b74d6b3ca..b1064a0c5e62 100644 --- a/tools/testing/selftests/kvm/lib/aarch64/processor.c +++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c@@ -216,6 +216,7 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, int vcpuid, struct kvm_vcpu_init *ini { struct kvm_vcpu_init default_init = { .target = -1, }; uint64_t sctlr_el1, tcr_el1; + int ret; if (!init) init = &default_init;@@ -226,7 +227,19 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, int vcpuid, struct kvm_vcpu_init *ini init->target = preferred.target; } - vcpu_ioctl(vm, vcpuid, KVM_ARM_VCPU_INIT, init); + ret = _vcpu_ioctl(vm, vcpuid, KVM_ARM_VCPU_INIT, init); + + /* + * Missing kernel feature support should result in skipping the test, + * not failing it. + */ + if (ret && errno == ENOENT) { + print_skip("requested vCPU features not supported; skipping test.");
", skipping test" will already be appended by print_skip().
+ exit(KSFT_SKIP); + } + + TEST_ASSERT(!ret, "KVM_ARM_VCPU_INIT failed, rc: %i errno: %i (%s)", + ret, errno, strerror(errno)); /* * Enable FP/ASIMD to avoid trapping when accessing Q0-Q15 -- 2.33.0.rc1.237.g0d66db33f3-goog
I think I'd rather try to keep exit(KSFT_SKIP)'s out of the lib code. It'd be better if the test gets to decide whether to skip or not. How about moving this check+skip into the test instead? Thanks, drew