[PATCH v5 12/13] selftests: KVM: Test physical counter offsetting

From: Oliver Upton <oupton@google.com>
To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	Marc Zyngier <maz@kernel.org>, Peter Shier <pshier@google.com>,
	Jim Mattson <jmattson@google.com>,
	David Matlack <dmatlack@google.com>,
	Ricardo Koller <ricarkol@google.com>,
	Jing Zhang <jingzhangos@google.com>,
	Raghavendra Rao Anata <rananta@google.com>,
	James Morse <james.morse@arm.com>,
	Alexandru Elisei <alexandru.elisei@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	linux-arm-kernel@lists.infradead.org,
	Andrew Jones <drjones@redhat.com>,
	Oliver Upton <oupton@google.com>
Subject: [PATCH v5 12/13] selftests: KVM: Test physical counter offsetting
Date: Thu, 29 Jul 2021 17:32:59 +0000	[thread overview]
Message-ID: <20210729173300.181775-13-oupton@google.com> (raw)
In-Reply-To: <20210729173300.181775-1-oupton@google.com>

Test that userpace adjustment of the guest physical counter-timer
results in the correct view of within the guest.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Oliver Upton <oupton@google.com>
---
 .../selftests/kvm/include/aarch64/processor.h | 12 ++++++++
 .../kvm/system_counter_offset_test.c          | 29 ++++++++++++++++---
 2 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h
index 3168cdbae6ee..7f53d90e9512 100644
--- a/tools/testing/selftests/kvm/include/aarch64/processor.h
+++ b/tools/testing/selftests/kvm/include/aarch64/processor.h
@@ -141,4 +141,16 @@ static inline uint64_t read_cntvct_ordered(void)
 	return r;
 }
 
+static inline uint64_t read_cntpct_ordered(void)
+{
+	uint64_t r;
+
+	__asm__ __volatile__("isb\n\t"
+			     "mrs %0, cntpct_el0\n\t"
+			     "isb\n\t"
+			     : "=r"(r));
+
+	return r;
+}
+
 #endif /* SELFTEST_KVM_PROCESSOR_H */
diff --git a/tools/testing/selftests/kvm/system_counter_offset_test.c b/tools/testing/selftests/kvm/system_counter_offset_test.c
index 25806cdd31ef..ef215fb43657 100644
--- a/tools/testing/selftests/kvm/system_counter_offset_test.c
+++ b/tools/testing/selftests/kvm/system_counter_offset_test.c
@@ -57,6 +57,7 @@ static uint64_t host_read_guest_system_counter(struct test_case *test)
 
 enum arch_counter {
 	VIRTUAL,
+	PHYSICAL,
 };
 
 struct test_case {
@@ -68,23 +69,41 @@ static struct test_case test_cases[] = {
 	{ .counter = VIRTUAL, .offset = 0 },
 	{ .counter = VIRTUAL, .offset = 180 * NSEC_PER_SEC },
 	{ .counter = VIRTUAL, .offset = -180 * NSEC_PER_SEC },
+	{ .counter = PHYSICAL, .offset = 0 },
+	{ .counter = PHYSICAL, .offset = 180 * NSEC_PER_SEC },
+	{ .counter = PHYSICAL, .offset = -180 * NSEC_PER_SEC },
 };
 
 static void check_preconditions(struct kvm_vm *vm)
 {
 	if (!_vcpu_has_device_attr(vm, VCPU_ID, KVM_ARM_VCPU_TIMER_CTRL,
-				   KVM_ARM_VCPU_TIMER_OFFSET_VTIMER))
+				   KVM_ARM_VCPU_TIMER_OFFSET_VTIMER) &&
+	    !_vcpu_has_device_attr(vm, VCPU_ID, KVM_ARM_VCPU_TIMER_CTRL,
+				   KVM_ARM_VCPU_TIMER_OFFSET_PTIMER))
 		return;
 
-	print_skip("KVM_ARM_VCPU_TIMER_OFFSET_VTIMER not supported; skipping test");
+	print_skip("KVM_ARM_VCPU_TIMER_OFFSET_{VTIMER,PTIMER} not supported; skipping test");
 	exit(KSFT_SKIP);
 }
 
 static void setup_system_counter(struct kvm_vm *vm, struct test_case *test)
 {
+	u64 attr = 0;
+
+	switch (test->counter) {
+	case VIRTUAL:
+		attr = KVM_ARM_VCPU_TIMER_OFFSET_VTIMER;
+		break;
+	case PHYSICAL:
+		attr = KVM_ARM_VCPU_TIMER_OFFSET_PTIMER;
+		break;
+	default:
+		TEST_ASSERT(false, "unrecognized counter index %u",
+			    test->counter);
+	}
+
 	vcpu_access_device_attr(vm, VCPU_ID, KVM_ARM_VCPU_TIMER_CTRL,
-				KVM_ARM_VCPU_TIMER_OFFSET_VTIMER, &test->offset,
-				true);
+				attr, &test->offset, true);
 }
 
 static uint64_t guest_read_system_counter(struct test_case *test)
@@ -92,6 +111,8 @@ static uint64_t guest_read_system_counter(struct test_case *test)
 	switch (test->counter) {
 	case VIRTUAL:
 		return read_cntvct_ordered();
+	case PHYSICAL:
+		return read_cntpct_ordered();
 	default:
 		GUEST_ASSERT(0);
 	}
-- 
2.32.0.432.gabb21c7263-goog

