Merge tag 'kvm-x86-selftests-6.8-rcN' of https://github.com/kvm-x86/linux into HEAD

KVM selftests fixes/cleanups (and one KVM x86 cleanup) for 6.8:

 - Remove redundant newlines from error messages.

 - Delete an unused variable in the AMX test (which causes build failures when
   compiling with -Werror).

 - Fail instead of skipping tests if open(), e.g. of /dev/kvm, fails with an
   error code other than ENOENT (a Hyper-V selftest bug resulted in an EMFILE,
   and the test eventually got skipped).

 - Fix TSC related bugs in several Hyper-V selftests.

 - Fix a bug in the dirty ring logging test where a sem_post() could be left
   pending across multiple runs, resulting in incorrect synchronization between
   the main thread and the vCPU worker thread.

 - Relax the dirty log split test's assertions on 4KiB mappings to fix false
   positives due to the number of mappings for memslot 0 (used for code and
   data that is NOT being dirty logged) changing, e.g. due to NUMA balancing.

 - Have KVM's gtod_is_based_on_tsc() return "bool" instead of an "int" (the
   function generates boolean values, and all callers treat the return value as
   a bool).

58 files changed, 236 insertions, 239 deletions

diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
index 274b8465b42a..2cb8dd1f8275 100644
--- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
+++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
@@ -248,7 +248,7 @@ static void *test_vcpu_run(void *arg)
 		REPORT_GUEST_ASSERT(uc);
 		break;
 	default:
-		TEST_FAIL("Unexpected guest exit\n");
+		TEST_FAIL("Unexpected guest exit");
 	}
 
 	return NULL;
@@ -287,7 +287,7 @@ static int test_migrate_vcpu(unsigned int vcpu_idx)
 
 	/* Allow the error where the vCPU thread is already finished */
 	TEST_ASSERT(ret == 0 || ret == ESRCH,
-		    "Failed to migrate the vCPU:%u to pCPU: %u; ret: %d\n",
+		    "Failed to migrate the vCPU:%u to pCPU: %u; ret: %d",
 		    vcpu_idx, new_pcpu, ret);
 
 	return ret;
@@ -326,12 +326,12 @@ static void test_run(struct kvm_vm *vm)
 
 	pthread_mutex_init(&vcpu_done_map_lock, NULL);
 	vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
-	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap\n");
+	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap");
 
 	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
 		ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
 				     (void *)(unsigned long)i);
-		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread\n", i);
+		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread", i);
 	}
 
 	/* Spawn a thread to control the vCPU migrations */
@@ -340,7 +340,7 @@ static void test_run(struct kvm_vm *vm)
 
 		ret = pthread_create(&pt_vcpu_migration, NULL,
 					test_vcpu_migration, NULL);
-		TEST_ASSERT(!ret, "Failed to create the migration pthread\n");
+		TEST_ASSERT(!ret, "Failed to create the migration pthread");
 	}
 
 
@@ -384,7 +384,7 @@ static struct kvm_vm *test_vm_create(void)
 		if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET))
 			vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &test_args.offset);
 		else
-			TEST_FAIL("no support for global offset\n");
+			TEST_FAIL("no support for global offset");
 	}
 
 	for (i = 0; i < nr_vcpus; i++)
diff --git a/tools/testing/selftests/kvm/aarch64/hypercalls.c b/tools/testing/selftests/kvm/aarch64/hypercalls.c
index 31f66ba97228..27c10e7a7e01 100644
--- a/tools/testing/selftests/kvm/aarch64/hypercalls.c
+++ b/tools/testing/selftests/kvm/aarch64/hypercalls.c
@@ -175,18 +175,18 @@ static void test_fw_regs_before_vm_start(struct kvm_vcpu *vcpu)
 		/* First 'read' should be an upper limit of the features supported */
 		vcpu_get_reg(vcpu, reg_info->reg, &val);
 		TEST_ASSERT(val == FW_REG_ULIMIT_VAL(reg_info->max_feat_bit),
-			"Expected all the features to be set for reg: 0x%lx; expected: 0x%lx; read: 0x%lx\n",
+			"Expected all the features to be set for reg: 0x%lx; expected: 0x%lx; read: 0x%lx",
 			reg_info->reg, FW_REG_ULIMIT_VAL(reg_info->max_feat_bit), val);
 
 		/* Test a 'write' by disabling all the features of the register map */
 		ret = __vcpu_set_reg(vcpu, reg_info->reg, 0);
 		TEST_ASSERT(ret == 0,
-			"Failed to clear all the features of reg: 0x%lx; ret: %d\n",
+			"Failed to clear all the features of reg: 0x%lx; ret: %d",
 			reg_info->reg, errno);
 
 		vcpu_get_reg(vcpu, reg_info->reg, &val);
 		TEST_ASSERT(val == 0,
-			"Expected all the features to be cleared for reg: 0x%lx\n", reg_info->reg);
+			"Expected all the features to be cleared for reg: 0x%lx", reg_info->reg);
 
 		/*
 		 * Test enabling a feature that's not supported.
@@ -195,7 +195,7 @@ static void test_fw_regs_before_vm_start(struct kvm_vcpu *vcpu)
 		if (reg_info->max_feat_bit < 63) {
 			ret = __vcpu_set_reg(vcpu, reg_info->reg, BIT(reg_info->max_feat_bit + 1));
 			TEST_ASSERT(ret != 0 && errno == EINVAL,
-			"Unexpected behavior or return value (%d) while setting an unsupported feature for reg: 0x%lx\n",
+			"Unexpected behavior or return value (%d) while setting an unsupported feature for reg: 0x%lx",
 			errno, reg_info->reg);
 		}
 	}
@@ -216,7 +216,7 @@ static void test_fw_regs_after_vm_start(struct kvm_vcpu *vcpu)
 		 */
 		vcpu_get_reg(vcpu, reg_info->reg, &val);
 		TEST_ASSERT(val == 0,
-			"Expected all the features to be cleared for reg: 0x%lx\n",
+			"Expected all the features to be cleared for reg: 0x%lx",
 			reg_info->reg);
 
 		/*
@@ -226,7 +226,7 @@ static void test_fw_regs_after_vm_start(struct kvm_vcpu *vcpu)
 		 */
 		ret = __vcpu_set_reg(vcpu, reg_info->reg, FW_REG_ULIMIT_VAL(reg_info->max_feat_bit));
 		TEST_ASSERT(ret != 0 && errno == EBUSY,
-		"Unexpected behavior or return value (%d) while setting a feature while VM is running for reg: 0x%lx\n",
+		"Unexpected behavior or return value (%d) while setting a feature while VM is running for reg: 0x%lx",
 		errno, reg_info->reg);
 	}
 }
@@ -265,7 +265,7 @@ static void test_guest_stage(struct kvm_vm **vm, struct kvm_vcpu **vcpu)
 	case TEST_STAGE_HVC_IFACE_FALSE_INFO:
 		break;
 	default:
-		TEST_FAIL("Unknown test stage: %d\n", prev_stage);
+		TEST_FAIL("Unknown test stage: %d", prev_stage);
 	}
 }
 
@@ -294,7 +294,7 @@ static void test_run(void)
 			REPORT_GUEST_ASSERT(uc);
 			break;
 		default:
-			TEST_FAIL("Unexpected guest exit\n");
+			TEST_FAIL("Unexpected guest exit");
 		}
 	}
 
diff --git a/tools/testing/selftests/kvm/aarch64/page_fault_test.c b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
index 08a5ca5bed56..53fddad57cbb 100644
--- a/tools/testing/selftests/kvm/aarch64/page_fault_test.c
+++ b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
@@ -414,10 +414,10 @@ static bool punch_hole_in_backing_store(struct kvm_vm *vm,
 	if (fd != -1) {
 		ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
 				0, paging_size);
-		TEST_ASSERT(ret == 0, "fallocate failed\n");
+		TEST_ASSERT(ret == 0, "fallocate failed");
 	} else {
 		ret = madvise(hva, paging_size, MADV_DONTNEED);
-		TEST_ASSERT(ret == 0, "madvise failed\n");
+		TEST_ASSERT(ret == 0, "madvise failed");
 	}
 
 	return true;
@@ -501,7 +501,7 @@ static bool handle_cmd(struct kvm_vm *vm, int cmd)
 
 void fail_vcpu_run_no_handler(int ret)
 {
-	TEST_FAIL("Unexpected vcpu run failure\n");
+	TEST_FAIL("Unexpected vcpu run failure");
 }
 
 void fail_vcpu_run_mmio_no_syndrome_handler(int ret)
diff --git a/tools/testing/selftests/kvm/aarch64/smccc_filter.c b/tools/testing/selftests/kvm/aarch64/smccc_filter.c
index f4ceae9c8925..2d189f3da228 100644
--- a/tools/testing/selftests/kvm/aarch64/smccc_filter.c
+++ b/tools/testing/selftests/kvm/aarch64/smccc_filter.c
@@ -178,7 +178,7 @@ static void expect_call_denied(struct kvm_vcpu *vcpu)
 	struct ucall uc;
 
 	if (get_ucall(vcpu, &uc) != UCALL_SYNC)
-		TEST_FAIL("Unexpected ucall: %lu\n", uc.cmd);
+		TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
 
 	TEST_ASSERT(uc.args[1] == SMCCC_RET_NOT_SUPPORTED,
 		    "Unexpected SMCCC return code: %lu", uc.args[1]);
diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
index 9d51b5691349..5f9713364693 100644
--- a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
+++ b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
@@ -517,11 +517,11 @@ static void test_create_vpmu_vm_with_pmcr_n(uint64_t pmcr_n, bool expect_fail)
 
 	if (expect_fail)
 		TEST_ASSERT(pmcr_orig == pmcr,
-			    "PMCR.N modified by KVM to a larger value (PMCR: 0x%lx) for pmcr_n: 0x%lx\n",
+			    "PMCR.N modified by KVM to a larger value (PMCR: 0x%lx) for pmcr_n: 0x%lx",
 			    pmcr, pmcr_n);
 	else
 		TEST_ASSERT(pmcr_n == get_pmcr_n(pmcr),
-			    "Failed to update PMCR.N to %lu (received: %lu)\n",
+			    "Failed to update PMCR.N to %lu (received: %lu)",
 			    pmcr_n, get_pmcr_n(pmcr));
 }
 
@@ -594,12 +594,12 @@ static void run_pmregs_validity_test(uint64_t pmcr_n)
 		 */
 		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(set_reg_id), &reg_val);
 		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,
-			    "Initial read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx\n",
+			    "Initial read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx",
 			    KVM_ARM64_SYS_REG(set_reg_id), reg_val);
 
 		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(clr_reg_id), &reg_val);
 		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,
-			    "Initial read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx\n",
+			    "Initial read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx",
 			    KVM_ARM64_SYS_REG(clr_reg_id), reg_val);
 
 		/*
@@ -611,12 +611,12 @@ static void run_pmregs_validity_test(uint64_t pmcr_n)
 
 		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(set_reg_id), &reg_val);
 		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,
-			    "Read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx\n",
+			    "Read of set_reg: 0x%llx has unimplemented counters enabled: 0x%lx",
 			    KVM_ARM64_SYS_REG(set_reg_id), reg_val);
 
 		vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(clr_reg_id), &reg_val);
 		TEST_ASSERT((reg_val & (~valid_counters_mask)) == 0,
-			    "Read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx\n",
+			    "Read of clr_reg: 0x%llx has unimplemented counters enabled: 0x%lx",
 			    KVM_ARM64_SYS_REG(clr_reg_id), reg_val);
 	}
 
diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 09c116a82a84..bf3609f71854 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -45,10 +45,10 @@ static void vcpu_worker(struct memstress_vcpu_args *vcpu_args)
 
 	/* Let the guest access its memory */
 	ret = _vcpu_run(vcpu);
-	TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
+	TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret);
 	if (get_ucall(vcpu, NULL) != UCALL_SYNC) {
 		TEST_ASSERT(false,
-			    "Invalid guest sync status: exit_reason=%s\n",
+			    "Invalid guest sync status: exit_reason=%s",
 			    exit_reason_str(run->exit_reason));
 	}
 
diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
index d374dbcf9a53..504f6fe980e8 100644
--- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
@@ -88,9 +88,9 @@ static void vcpu_worker(struct memstress_vcpu_args *vcpu_args)
 		ret = _vcpu_run(vcpu);
 		ts_diff = timespec_elapsed(start);
 
-		TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
+		TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret);
 		TEST_ASSERT(get_ucall(vcpu, NULL) == UCALL_SYNC,
-			    "Invalid guest sync status: exit_reason=%s\n",
+			    "Invalid guest sync status: exit_reason=%s",
 			    exit_reason_str(run->exit_reason));
 
 		pr_debug("Got sync event from vCPU %d\n", vcpu_idx);
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index 6cbecf499767..eaad5b20854c 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -262,7 +262,7 @@ static void default_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
 		    "vcpu run failed: errno=%d", err);
 
 	TEST_ASSERT(get_ucall(vcpu, NULL) == UCALL_SYNC,
-		    "Invalid guest sync status: exit_reason=%s\n",
+		    "Invalid guest sync status: exit_reason=%s",
 		    exit_reason_str(run->exit_reason));
 
 	vcpu_handle_sync_stop();
@@ -376,7 +376,10 @@ static void dirty_ring_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
 
 	cleared = kvm_vm_reset_dirty_ring(vcpu->vm);
 
-	/* Cleared pages should be the same as collected */
+	/*
+	 * Cleared pages should be the same as collected, as KVM is supposed to
+	 * clear only the entries that have been harvested.
+	 */
 	TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch "
 		    "with collected (%u)", cleared, count);
 
@@ -410,17 +413,11 @@ static void dirty_ring_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
 		pr_info("vcpu continues now.\n");
 	} else {
 		TEST_ASSERT(false, "Invalid guest sync status: "
-			    "exit_reason=%s\n",
+			    "exit_reason=%s",
 			    exit_reason_str(run->exit_reason));
 	}
 }
 
-static void dirty_ring_before_vcpu_join(void)
-{
-	/* Kick another round of vcpu just to make sure it will quit */
-	sem_post(&sem_vcpu_cont);
-}
-
 struct log_mode {
 	const char *name;
 	/* Return true if this mode is supported, otherwise false */
@@ -433,7 +430,6 @@ struct log_mode {
 				     uint32_t *ring_buf_idx);
 	/* Hook to call when after each vcpu run */
 	void (*after_vcpu_run)(struct kvm_vcpu *vcpu, int ret, int err);
-	void (*before_vcpu_join) (void);
 } log_modes[LOG_MODE_NUM] = {
 	{
 		.name = "dirty-log",
@@ -452,7 +448,6 @@ struct log_mode {
 		.supported = dirty_ring_supported,
 		.create_vm_done = dirty_ring_create_vm_done,
 		.collect_dirty_pages = dirty_ring_collect_dirty_pages,
-		.before_vcpu_join = dirty_ring_before_vcpu_join,
 		.after_vcpu_run = dirty_ring_after_vcpu_run,
 	},
 };
@@ -513,14 +508,6 @@ static void log_mode_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
 		mode->after_vcpu_run(vcpu, ret, err);
 }
 
-static void log_mode_before_vcpu_join(void)
-{
-	struct log_mode *mode = &log_modes[host_log_mode];
-
-	if (mode->before_vcpu_join)
-		mode->before_vcpu_join();
-}
-
 static void generate_random_array(uint64_t *guest_array, uint64_t size)
 {
 	uint64_t i;
@@ -719,6 +706,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	struct kvm_vm *vm;
 	unsigned long *bmap;
 	uint32_t ring_buf_idx = 0;
+	int sem_val;
 
 	if (!log_mode_supported()) {
 		print_skip("Log mode '%s' not supported",
@@ -788,12 +776,22 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	/* Start the iterations */
 	iteration = 1;
 	sync_global_to_guest(vm, iteration);
-	host_quit = false;
+	WRITE_ONCE(host_quit, false);
 	host_dirty_count = 0;
 	host_clear_count = 0;
 	host_track_next_count = 0;
 	WRITE_ONCE(dirty_ring_vcpu_ring_full, false);
 
+	/*
+	 * Ensure the previous iteration didn't leave a dangling semaphore, i.e.
+	 * that the main task and vCPU worker were synchronized and completed
+	 * verification of all iterations.
+	 */
+	sem_getvalue(&sem_vcpu_stop, &sem_val);
+	TEST_ASSERT_EQ(sem_val, 0);
+	sem_getvalue(&sem_vcpu_cont, &sem_val);
+	TEST_ASSERT_EQ(sem_val, 0);
+
 	pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);
 
 	while (iteration < p->iterations) {
@@ -819,15 +817,21 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 		assert(host_log_mode == LOG_MODE_DIRTY_RING ||
 		       atomic_read(&vcpu_sync_stop_requested) == false);
 		vm_dirty_log_verify(mode, bmap);
-		sem_post(&sem_vcpu_cont);
 
-		iteration++;
+		/*
+		 * Set host_quit before sem_vcpu_cont in the final iteration to
+		 * ensure that the vCPU worker doesn't resume the guest.  As
+		 * above, the dirty ring test may stop and wait even when not
+		 * explicitly request to do so, i.e. would hang waiting for a
+		 * "continue" if it's allowed to resume the guest.
+		 */
+		if (++iteration == p->iterations)
+			WRITE_ONCE(host_quit, true);
+
+		sem_post(&sem_vcpu_cont);
 		sync_global_to_guest(vm, iteration);
 	}
 
-	/* Tell the vcpu thread to quit */
-	host_quit = true;
-	log_mode_before_vcpu_join();
 	pthread_join(vcpu_thread, NULL);
 
 	pr_info("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), "
diff --git a/tools/testing/selftests/kvm/get-reg-list.c b/tools/testing/selftests/kvm/get-reg-list.c
index 8274ef04301f..91f05f78e824 100644
--- a/tools/testing/selftests/kvm/get-reg-list.c
+++ b/tools/testing/selftests/kvm/get-reg-list.c
@@ -152,7 +152,7 @@ static void check_supported(struct vcpu_reg_list *c)
 			continue;
 
 		__TEST_REQUIRE(kvm_has_cap(s->capability),
-			       "%s: %s not available, skipping tests\n",
+			       "%s: %s not available, skipping tests",
 			       config_name(c), s->name);
 	}
 }
diff --git a/tools/testing/selftests/kvm/guest_print_test.c b/tools/testing/selftests/kvm/guest_print_test.c
index 41230b746190..3502caa3590c 100644
--- a/tools/testing/selftests/kvm/guest_print_test.c
+++ b/tools/testing/selftests/kvm/guest_print_test.c
@@ -98,7 +98,7 @@ static void ucall_abort(const char *assert_msg, const char *expected_assert_msg)
 	int offset = len_str - len_substr;
 
 	TEST_ASSERT(len_substr <= len_str,
-		    "Expected '%s' to be a substring of '%s'\n",
+		    "Expected '%s' to be a substring of '%s'",
 		    assert_msg, expected_assert_msg);
 
 	TEST_ASSERT(strcmp(&assert_msg[offset], expected_assert_msg) == 0,
@@ -116,7 +116,7 @@ static void run_test(struct kvm_vcpu *vcpu, const char *expected_printf,
 		vcpu_run(vcpu);
 
 		TEST_ASSERT(run->exit_reason == UCALL_EXIT_REASON,
-			    "Unexpected exit reason: %u (%s),\n",
+			    "Unexpected exit reason: %u (%s),",
 			    run->exit_reason, exit_reason_str(run->exit_reason));
 
 		switch (get_ucall(vcpu, &uc)) {
@@ -161,11 +161,11 @@ static void test_limits(void)
 	vcpu_run(vcpu);
 
 	TEST_ASSERT(run->exit_reason == UCALL_EXIT_REASON,
-		    "Unexpected exit reason: %u (%s),\n",
+		    "Unexpected exit reason: %u (%s),",
 		    run->exit_reason, exit_reason_str(run->exit_reason));
 
 	TEST_ASSERT(get_ucall(vcpu, &uc) == UCALL_ABORT,
-		    "Unexpected ucall command: %lu,  Expected: %u (UCALL_ABORT)\n",
+		    "Unexpected ucall command: %lu,  Expected: %u (UCALL_ABORT)",
 		    uc.cmd, UCALL_ABORT);
 
 	kvm_vm_free(vm);
diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c
index f5d59b9934f1..decc521fc760 100644
--- a/tools/testing/selftests/kvm/hardware_disable_test.c
+++ b/tools/testing/selftests/kvm/hardware_disable_test.c
@@ -41,7 +41,7 @@ static void *run_vcpu(void *arg)
 
 	vcpu_run(vcpu);
 
-	TEST_ASSERT(false, "%s: exited with reason %d: %s\n",
+	TEST_ASSERT(false, "%s: exited with reason %d: %s",
 		    __func__, run->exit_reason,
 		    exit_reason_str(run->exit_reason));
 	pthread_exit(NULL);
@@ -55,7 +55,7 @@ static void *sleeping_thread(void *arg)
 		fd = open("/dev/null", O_RDWR);
 		close(fd);
 	}
-	TEST_ASSERT(false, "%s: exited\n", __func__);
+	TEST_ASSERT(false, "%s: exited", __func__);
 	pthread_exit(NULL);
 }
 
@@ -118,7 +118,7 @@ static void run_test(uint32_t run)
 	for (i = 0; i < VCPU_NUM; ++i)
 		check_join(threads[i], &b);
 	/* Should not be reached */
-	TEST_ASSERT(false, "%s: [%d] child escaped the ninja\n", __func__, run);
+	TEST_ASSERT(false, "%s: [%d] child escaped the ninja", __func__, run);
 }
 
 void wait_for_child_setup(pid_t pid)
diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h
index 71a41fa924b7..50a5e31ba8da 100644
--- a/tools/testing/selftests/kvm/include/test_util.h
+++ b/tools/testing/selftests/kvm/include/test_util.h
@@ -195,4 +195,6 @@ __printf(3, 4) int guest_snprintf(char *buf, int n, const char *fmt, ...);
 
 char *strdup_printf(const char *fmt, ...) __attribute__((format(printf, 1, 2), nonnull(1)));
 
+char *sys_get_cur_clocksource(void);
+
 #endif /* SELFTEST_KVM_TEST_UTIL_H */
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index a84863503fcb..5bca8c947c82 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -1271,4 +1271,6 @@ void virt_map_level(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 #define PFERR_GUEST_PAGE_MASK	BIT_ULL(PFERR_GUEST_PAGE_BIT)
 #define PFERR_IMPLICIT_ACCESS	BIT_ULL(PFERR_IMPLICIT_ACCESS_BIT)
 
+bool sys_clocksource_is_based_on_tsc(void);
+
 #endif /* SELFTEST_KVM_PROCESSOR_H */
diff --git a/tools/testing/selftests/kvm/kvm_create_max_vcpus.c b/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
index 31b3cb24b9a7..b9e23265e4b3 100644
--- a/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
+++ b/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 
 			int r = setrlimit(RLIMIT_NOFILE, &rl);
 			__TEST_REQUIRE(r >= 0,
-				       "RLIMIT_NOFILE hard limit is too low (%d, wanted %d)\n",
+				       "RLIMIT_NOFILE hard limit is too low (%d, wanted %d)",
 				       old_rlim_max, nr_fds_wanted);
 		} else {
 			TEST_ASSERT(!setrlimit(RLIMIT_NOFILE, &rl), "setrlimit() failed!");
diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
index e37dc9c21888..e0ba97ac1c56 100644
--- a/tools/testing/selftests/kvm/kvm_page_table_test.c
+++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
@@ -204,9 +204,9 @@ static void *vcpu_worker(void *data)
 		ret = _vcpu_run(vcpu);
 		ts_diff = timespec_elapsed(start);
 
-		TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
+		TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret);
 		TEST_ASSERT(get_ucall(vcpu, NULL) == UCALL_SYNC,
-			    "Invalid guest sync status: exit_reason=%s\n",
+			    "Invalid guest sync status: exit_reason=%s",
 			    exit_reason_str(vcpu->run->exit_reason));
 
 		pr_debug("Got sync event from vCPU %d\n", vcpu->id);
diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
index 41c776b642c0..43b9a7283360 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
@@ -398,7 +398,7 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
 	int i;
 
 	TEST_ASSERT(num >= 1 && num <= 8, "Unsupported number of args,\n"
-		    "  num: %u\n", num);
+		    "  num: %u", num);
 
 	va_start(ap, num);
 
diff --git a/tools/testing/selftests/kvm/lib/aarch64/vgic.c b/tools/testing/selftests/kvm/lib/aarch64/vgic.c
index b5f28d21a947..184378d593e9 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/vgic.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/vgic.c
@@ -38,7 +38,7 @@ int vgic_v3_setup(struct kvm_vm *vm, unsigned int nr_vcpus, uint32_t nr_irqs,
 	struct list_head *iter;
 	unsigned int nr_gic_pages, nr_vcpus_created = 0;
 
-	TEST_ASSERT(nr_vcpus, "Number of vCPUs cannot be empty\n");
+	TEST_ASSERT(nr_vcpus, "Number of vCPUs cannot be empty");
 
 	/*
 	 * Make sure that the caller is infact calling this
@@ -47,7 +47,7 @@ int vgic_v3_setup(struct kvm_vm *vm, unsigned int nr_vcpus, uint32_t nr_irqs,
 	list_for_each(iter, &vm->vcpus)
 		nr_vcpus_created++;
 	TEST_ASSERT(nr_vcpus == nr_vcpus_created,
-			"Number of vCPUs requested (%u) doesn't match with the ones created for the VM (%u)\n",
+			"Number of vCPUs requested (%u) doesn't match with the ones created for the VM (%u)",
 			nr_vcpus, nr_vcpus_created);
 
 	/* Distributor setup */
diff --git a/tools/testing/selftests/kvm/lib/elf.c b/tools/testing/selftests/kvm/lib/elf.c
index 266f3876e10a..f34d926d9735 100644
--- a/tools/testing/selftests/kvm/lib/elf.c
+++ b/tools/testing/selftests/kvm/lib/elf.c
@@ -184,7 +184,7 @@ void kvm_vm_elf_load(struct kvm_vm *vm, const char *filename)
 				"Seek to program segment offset failed,\n"
 				"  program header idx: %u errno: %i\n"
 				"  offset_rv: 0x%jx\n"
-				"  expected: 0x%jx\n",
+				"  expected: 0x%jx",
 				n1, errno, (intmax_t) offset_rv,
 				(intmax_t) phdr.p_offset);
 			test_read(fd, addr_gva2hva(vm, phdr.p_vaddr),
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index e066d584c656..1b197426f29f 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -27,7 +27,8 @@ int open_path_or_exit(const char *path, int flags)
 	int fd;
 
 	fd = open(path, flags);
-	__TEST_REQUIRE(fd >= 0, "%s not available (errno: %d)", path, errno);
+	__TEST_REQUIRE(fd >= 0 || errno != ENOENT, "Cannot open %s: %s", path, strerror(errno));
+	TEST_ASSERT(fd >= 0, "Failed to open '%s'", path);
 
 	return fd;
 }
@@ -320,7 +321,7 @@ static uint64_t vm_nr_pages_required(enum vm_guest_mode mode,
 	uint64_t nr_pages;
 
 	TEST_ASSERT(nr_runnable_vcpus,
-		    "Use vm_create_barebones() for VMs that _never_ have vCPUs\n");
+		    "Use vm_create_barebones() for VMs that _never_ have vCPUs");
 
 	TEST_ASSERT(nr_runnable_vcpus <= kvm_check_cap(KVM_CAP_MAX_VCPUS),
 		    "nr_vcpus = %d too large for host, max-vcpus = %d",
@@ -491,7 +492,7 @@ void kvm_pin_this_task_to_pcpu(uint32_t pcpu)
 	CPU_ZERO(&mask);
 	CPU_SET(pcpu, &mask);
 	r = sched_setaffinity(0, sizeof(mask), &mask);
-	TEST_ASSERT(!r, "sched_setaffinity() failed for pCPU '%u'.\n", pcpu);
+	TEST_ASSERT(!r, "sched_setaffinity() failed for pCPU '%u'.", pcpu);
 }
 
 static uint32_t parse_pcpu(const char *cpu_str, const cpu_set_t *allowed_mask)
@@ -499,7 +500,7 @@ static uint32_t parse_pcpu(const char *cpu_str, const cpu_set_t *allowed_mask)
 	uint32_t pcpu = atoi_non_negative("CPU number", cpu_str);
 
 	TEST_ASSERT(CPU_ISSET(pcpu, allowed_mask),
-		    "Not allowed to run on pCPU '%d', check cgroups?\n", pcpu);
+		    "Not allowed to run on pCPU '%d', check cgroups?", pcpu);
 	return pcpu;
 }
 
@@ -529,7 +530,7 @@ void kvm_parse_vcpu_pinning(const char *pcpus_string, uint32_t vcpu_to_pcpu[],
 	int i, r;
 
 	cpu_list = strdup(pcpus_string);
-	TEST_ASSERT(cpu_list, "strdup() allocation failed.\n");
+	TEST_ASSERT(cpu_list, "strdup() allocation failed.");
 
 	r = sched_getaffinity(0, sizeof(allowed_mask), &allowed_mask);
 	TEST_ASSERT(!r, "sched_getaffinity() failed");
@@ -538,7 +539,7 @@ void kvm_parse_vcpu_pinning(const char *pcpus_string, uint32_t vcpu_to_pcpu[],
 
 	/* 1. Get all pcpus for vcpus. */
 	for (i = 0; i < nr_vcpus; i++) {
-		TEST_ASSERT(cpu, "pCPU not provided for vCPU '%d'\n", i);
+		TEST_ASSERT(cpu, "pCPU not provided for vCPU '%d'", i);
 		vcpu_to_pcpu[i] = parse_pcpu(cpu, &allowed_mask);
 		cpu = strtok(NULL, delim);
 	}
@@ -1057,7 +1058,7 @@ void vm_mem_add(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type,
 	TEST_ASSERT(ret == 0, "KVM_SET_USER_MEMORY_REGION2 IOCTL failed,\n"
 		"  rc: %i errno: %i\n"
 		"  slot: %u flags: 0x%x\n"
-		"  guest_phys_addr: 0x%lx size: 0x%lx guest_memfd: %d\n",
+		"  guest_phys_addr: 0x%lx size: 0x%lx guest_memfd: %d",
 		ret, errno, slot, flags,
 		guest_paddr, (uint64_t) region->region.memory_size,
 		region->region.guest_memfd);
@@ -1222,7 +1223,7 @@ void vm_guest_mem_fallocate(struct kvm_vm *vm, uint64_t base, uint64_t size,
 		len = min_t(uint64_t, end - gpa, region->region.memory_size - offset);
 
 		ret = fallocate(region->region.guest_memfd, mode, fd_offset, len);
-		TEST_ASSERT(!ret, "fallocate() failed to %s at %lx (len = %lu), fd = %d, mode = %x, offset = %lx\n",
+		TEST_ASSERT(!ret, "fallocate() failed to %s at %lx (len = %lu), fd = %d, mode = %x, offset = %lx",
 			    punch_hole ? "punch hole" : "allocate", gpa, len,
 			    region->region.guest_memfd, mode, fd_offset);
 	}
@@ -1265,7 +1266,7 @@ struct kvm_vcpu *__vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id)
 	struct kvm_vcpu *vcpu;
 
 	/* Confirm a vcpu with the specified id doesn't already exist. */
-	TEST_ASSERT(!vcpu_exists(vm, vcpu_id), "vCPU%d already exists\n", vcpu_id);
+	TEST_ASSERT(!vcpu_exists(vm, vcpu_id), "vCPU%d already exists", vcpu_id);
 
 	/* Allocate and initialize new vcpu structure. */
 	vcpu = calloc(1, sizeof(*vcpu));
diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c
index d05487e5a371..cf2c73971308 100644
--- a/tools/testing/selftests/kvm/lib/memstress.c
+++ b/tools/testing/selftests/kvm/lib/memstress.c
@@ -192,7 +192,7 @@ struct kvm_vm *memstress_create_vm(enum vm_guest_mode mode, int nr_vcpus,
 	TEST_ASSERT(guest_num_pages < region_end_gfn,
 		    "Requested more guest memory than address space allows.\n"
 		    "    guest pages: %" PRIx64 " max gfn: %" PRIx64
-		    " nr_vcpus: %d wss: %" PRIx64 "]\n",
+		    " nr_vcpus: %d wss: %" PRIx64 "]",
 		    guest_num_pages, region_end_gfn - 1, nr_vcpus, vcpu_memory_bytes);
 
 	args->gpa = (region_end_gfn - guest_num_pages - 1) * args->guest_page_size;
diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c
index 7ca736fb4194..2bb33a8ac03c 100644
--- a/tools/testing/selftests/kvm/lib/riscv/processor.c
+++ b/tools/testing/selftests/kvm/lib/riscv/processor.c
@@ -327,7 +327,7 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
 	int i;
 
 	TEST_ASSERT(num >= 1 && num <= 8, "Unsupported number of args,\n"
-		    "  num: %u\n", num);
+		    "  num: %u", num);
 
 	va_start(ap, num);
 
diff --git a/tools/testing/selftests/kvm/lib/s390x/processor.c b/tools/testing/selftests/kvm/lib/s390x/processor.c
index 15945121daf1..f6d227892cbc 100644
--- a/tools/testing/selftests/kvm/lib/s390x/processor.c
+++ b/tools/testing/selftests/kvm/lib/s390x/processor.c
@@ -198,7 +198,7 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
 	int i;
 
 	TEST_ASSERT(num >= 1 && num <= 5, "Unsupported number of args,\n"
-		    "  num: %u\n",
+		    "  num: %u",
 		    num);
 
 	va_start(ap, num);
diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
index 5d7f28b02d73..5a8f8becb129 100644
--- a/tools/testing/selftests/kvm/lib/test_util.c
+++ b/tools/testing/selftests/kvm/lib/test_util.c
@@ -392,3 +392,28 @@ char *strdup_printf(const char *fmt, ...)
 
 	return str;
 }
+
+#define CLOCKSOURCE_PATH "/sys/devices/system/clocksource/clocksource0/current_clocksource"
+
+char *sys_get_cur_clocksource(void)
+{
+	char *clk_name;
+	struct stat st;
+	FILE *fp;
+
+	fp = fopen(CLOCKSOURCE_PATH, "r");
+	TEST_ASSERT(fp, "failed to open clocksource file, errno: %d", errno);
+
+	TEST_ASSERT(!fstat(fileno(fp), &st), "failed to stat clocksource file, errno: %d",
+		    errno);
+
+	clk_name = malloc(st.st_size);
+	TEST_ASSERT(clk_name, "failed to allocate buffer to read file");
+
+	TEST_ASSERT(fgets(clk_name, st.st_size, fp), "failed to read clocksource file: %d",
+		    ferror(fp));
+
+	fclose(fp);
+
+	return clk_name;
+}
diff --git a/tools/testing/selftests/kvm/lib/userfaultfd_util.c b/tools/testing/selftests/kvm/lib/userfaultfd_util.c
index 271f63891581..f4eef6eb2dc2 100644
--- a/tools/testing/selftests/kvm/lib/userfaultfd_util.c
+++ b/tools/testing/selftests/kvm/lib/userfaultfd_util.c
@@ -69,7 +69,7 @@ static void *uffd_handler_thread_fn(void *arg)
 		if (pollfd[1].revents & POLLIN) {
 			r = read(pollfd[1].fd, &tmp_chr, 1);
 			TEST_ASSERT(r == 1,
-				    "Error reading pipefd in UFFD thread\n");
+				    "Error reading pipefd in UFFD thread");
 			break;
 		}
 
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index d8288374078e..f639b3e062e3 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -170,10 +170,10 @@ static uint64_t *virt_create_upper_pte(struct kvm_vm *vm,
 		 * this level.
 		 */
 		TEST_ASSERT(current_level != target_level,
-			    "Cannot create hugepage at level: %u, vaddr: 0x%lx\n",
+			    "Cannot create hugepage at level: %u, vaddr: 0x%lx",
 			    current_level, vaddr);
 		TEST_ASSERT(!(*pte & PTE_LARGE_MASK),
-			    "Cannot create page table at level: %u, vaddr: 0x%lx\n",
+			    "Cannot create page table at level: %u, vaddr: 0x%lx",
 			    current_level, vaddr);
 	}
 	return pte;
@@ -220,7 +220,7 @@ void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
 	/* Fill in page table entry. */
 	pte = virt_get_pte(vm, pde, vaddr, PG_LEVEL_4K);
 	TEST_ASSERT(!(*pte & PTE_PRESENT_MASK),
-		    "PTE already present for 4k page at vaddr: 0x%lx\n", vaddr);
+		    "PTE already present for 4k page at vaddr: 0x%lx", vaddr);
 	*pte = PTE_PRESENT_MASK | PTE_WRITABLE_MASK | (paddr & PHYSICAL_PAGE_MASK);
 }
 
@@ -253,7 +253,7 @@ static bool vm_is_target_pte(uint64_t *pte, int *level, int current_level)
 	if (*pte & PTE_LARGE_MASK) {
 		TEST_ASSERT(*level == PG_LEVEL_NONE ||
 			    *level == current_level,
-			    "Unexpected hugepage at level %d\n", current_level);
+			    "Unexpected hugepage at level %d", current_level);
 		*level = current_level;
 	}
 
@@ -825,7 +825,7 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
 	struct kvm_regs regs;
 
 	TEST_ASSERT(num >= 1 && num <= 6, "Unsupported number of args,\n"
-		    "  num: %u\n",
+		    "  num: %u",
 		    num);
 
 	va_start(ap, num);
@@ -1299,3 +1299,14 @@ void kvm_selftest_arch_init(void)
 	host_cpu_is_intel = this_cpu_is_intel();
 	host_cpu_is_amd = this_cpu_is_amd();
 }
+
+bool sys_clocksource_is_based_on_tsc(void)
+{
+	char *clk_name = sys_get_cur_clocksource();
+	bool ret = !strcmp(clk_name, "tsc\n") ||
+		   !strcmp(clk_name, "hyperv_clocksource_tsc_page\n");
+
+	free(clk_name);
+
+	return ret;
+}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/vmx.c b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
index 59d97531c9b1..089b8925b6b2 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/vmx.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
@@ -54,7 +54,7 @@ int vcpu_enable_evmcs(struct kvm_vcpu *vcpu)
 	/* KVM should return supported EVMCS version range */
 	TEST_ASSERT(((evmcs_ver >> 8) >= (evmcs_ver & 0xff)) &&
 		    (evmcs_ver & 0xff) > 0,
-		    "Incorrect EVMCS version range: %x:%x\n",
+		    "Incorrect EVMCS version range: %x:%x",
 		    evmcs_ver & 0xff, evmcs_ver >> 8);
 
 	return evmcs_ver;
@@ -387,10 +387,10 @@ static void nested_create_pte(struct kvm_vm *vm,
 		 * this level.
 		 */
 		TEST_ASSERT(current_level != target_level,
-			    "Cannot create hugepage at level: %u, nested_paddr: 0x%lx\n",
+			    "Cannot create hugepage at level: %u, nested_paddr: 0x%lx",
 			    current_level, nested_paddr);
 		TEST_ASSERT(!pte->page_size,
-			    "Cannot create page table at level: %u, nested_paddr: 0x%lx\n",
+			    "Cannot create page table at level: %u, nested_paddr: 0x%lx",
 			    current_level, nested_paddr);
 	}
 }
diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
index 9855c41ca811..156361966612 100644
--- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c
+++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
@@ -45,7 +45,7 @@ static void vcpu_worker(struct memstress_vcpu_args *vcpu_args)
 	/* Let the guest access its memory until a stop signal is received */
 	while (!READ_ONCE(memstress_args.stop_vcpus)) {
 		ret = _vcpu_run(vcpu);
-		TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
+		TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret);
 
 		if (get_ucall(vcpu, NULL) == UCALL_SYNC)
 			continue;
diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
index 8698d1ab60d0..579a64f97333 100644
--- a/tools/testing/selftests/kvm/memslot_perf_test.c
+++ b/tools/testing/selftests/kvm/memslot_perf_test.c
@@ -175,11 +175,11 @@ static void wait_for_vcpu(void)
 	struct timespec ts;
 
 	TEST_ASSERT(!clock_gettime(CLOCK_REALTIME, &ts),
-		    "clock_gettime() failed: %d\n", errno);
+		    "clock_gettime() failed: %d", errno);
 
 	ts.tv_sec += 2;
 	TEST_ASSERT(!sem_timedwait(&vcpu_ready, &ts),
-		    "sem_timedwait() failed: %d\n", errno);
+		    "sem_timedwait() failed: %d", errno);
 }
 
 static void *vm_gpa2hva(struct vm_data *data, uint64_t gpa, uint64_t *rempages)
@@ -336,7 +336,7 @@ static bool prepare_vm(struct vm_data *data, int nslots, uint64_t *maxslots,
 
 		gpa = vm_phy_pages_alloc(data->vm, npages, guest_addr, slot);
 		TEST_ASSERT(gpa == guest_addr,
-			    "vm_phy_pages_alloc() failed\n");
+			    "vm_phy_pages_alloc() failed");
 
 		data->hva_slots[slot - 1] = addr_gpa2hva(data->vm, guest_addr);
 		memset(data->hva_slots[slot - 1], 0, npages * guest_page_size);
diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c
index 4fd0f8951574..6435e7a65642 100644
--- a/tools/testing/selftests/kvm/riscv/get-reg-list.c
+++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c
@@ -177,7 +177,7 @@ void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
 
 		/* Double check whether the desired extension was enabled */
 		__TEST_REQUIRE(vcpu_has_ext(vcpu, feature),
-			       "%s not available, skipping tests\n", s->name);
+			       "%s not available, skipping tests", s->name);
 	}
 }
 
diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
index f74e76d03b7e..28f97fb52044 100644
--- a/tools/testing/selftests/kvm/rseq_test.c
+++ b/tools/testing/selftests/kvm/rseq_test.c
@@ -245,7 +245,7 @@ int main(int argc, char *argv[])
 		} while (snapshot != atomic_read(&seq_cnt));
 
 		TEST_ASSERT(rseq_cpu == cpu,
-			    "rseq CPU = %d, sched CPU = %d\n", rseq_cpu, cpu);
+			    "rseq CPU = %d, sched CPU = %d", rseq_cpu, cpu);
 	}
 
 	/*
@@ -256,7 +256,7 @@ int main(int argc, char *argv[])
 	 * migrations given the 1us+ delay in the migration task.
 	 */
 	TEST_ASSERT(i > (NR_TASK_MIGRATIONS / 2),
-		    "Only performed %d KVM_RUNs, task stalled too much?\n", i);
+		    "Only performed %d KVM_RUNs, task stalled too much?", i);
 
 	pthread_join(migration_thread, NULL);
 
diff --git a/tools/testing/selftests/kvm/s390x/resets.c b/tools/testing/selftests/kvm/s390x/resets.c
index e41e2cb8ffa9..357943f2bea8 100644
--- a/tools/testing/selftests/kvm/s390x/resets.c
+++ b/tools/testing/selftests/kvm/s390x/resets.c
@@ -78,7 +78,7 @@ static void assert_noirq(struct kvm_vcpu *vcpu)
 	 * (notably, the emergency call interrupt we have injected) should
 	 * be cleared by the resets, so this should be 0.
 	 */
-	TEST_ASSERT(irqs >= 0, "Could not fetch IRQs: errno %d\n", errno);
+	TEST_ASSERT(irqs >= 0, "Could not fetch IRQs: errno %d", errno);
 	TEST_ASSERT(!irqs, "IRQ pending");
 }
 
@@ -199,7 +199,7 @@ static void inject_irq(struct kvm_vcpu *vcpu)
 	irq->type = KVM_S390_INT_EMERGENCY;
 	irq->u.emerg.code = vcpu->id;
 	irqs = __vcpu_ioctl(vcpu, KVM_S390_SET_IRQ_STATE, &irq_state);
-	TEST_ASSERT(irqs >= 0, "Error injecting EMERGENCY IRQ errno %d\n", errno);
+	TEST_ASSERT(irqs >= 0, "Error injecting EMERGENCY IRQ errno %d", errno);
 }
 
 static struct kvm_vm *create_vm(struct kvm_vcpu **vcpu)
diff --git a/tools/testing/selftests/kvm/s390x/sync_regs_test.c b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
index 636a70ddac1e..43fb25ddc3ec 100644
--- a/tools/testing/selftests/kvm/s390x/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
@@ -39,13 +39,13 @@ static void guest_code(void)
 #define REG_COMPARE(reg) \
 	TEST_ASSERT(left->reg == right->reg, \
 		    "Register " #reg \
-		    " values did not match: 0x%llx, 0x%llx\n", \
+		    " values did not match: 0x%llx, 0x%llx", \
 		    left->reg, right->reg)
 
 #define REG_COMPARE32(reg) \
 	TEST_ASSERT(left->reg == right->reg, \
 		    "Register " #reg \
-		    " values did not match: 0x%x, 0x%x\n", \
+		    " values did not match: 0x%x, 0x%x", \
 		    left->reg, right->reg)
 
 
@@ -82,14 +82,14 @@ void test_read_invalid(struct kvm_vcpu *vcpu)
 	run->kvm_valid_regs = INVALID_SYNC_FIELD;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_valid_regs = 0;
 
 	run->kvm_valid_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_valid_regs = 0;
 }
@@ -103,14 +103,14 @@ void test_set_invalid(struct kvm_vcpu *vcpu)
 	run->kvm_dirty_regs = INVALID_SYNC_FIELD;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_dirty_regs = 0;
 
 	run->kvm_dirty_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_dirty_regs = 0;
 }
@@ -125,12 +125,12 @@ void test_req_and_verify_all_valid_regs(struct kvm_vcpu *vcpu)
 	/* Request and verify all valid register sets. */
 	run->kvm_valid_regs = TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vcpu);
-	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
+	TEST_ASSERT(rv == 0, "vcpu_run failed: %d", rv);
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
 	TEST_ASSERT(run->s390_sieic.icptcode == 4 &&
 		    (run->s390_sieic.ipa >> 8) == 0x83 &&
 		    (run->s390_sieic.ipb >> 16) == 0x501,
-		    "Unexpected interception code: ic=%u, ipa=0x%x, ipb=0x%x\n",
+		    "Unexpected interception code: ic=%u, ipa=0x%x, ipb=0x%x",
 		    run->s390_sieic.icptcode, run->s390_sieic.ipa,
 		    run->s390_sieic.ipb);
 
@@ -161,7 +161,7 @@ void test_set_and_verify_various_reg_values(struct kvm_vcpu *vcpu)
 	}
 
 	rv = _vcpu_run(vcpu);
-	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
+	TEST_ASSERT(rv == 0, "vcpu_run failed: %d", rv);
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
 	TEST_ASSERT(run->s.regs.gprs[11] == 0xBAD1DEA + 1,
 		    "r11 sync regs value incorrect 0x%llx.",
@@ -193,7 +193,7 @@ void test_clear_kvm_dirty_regs_bits(struct kvm_vcpu *vcpu)
 	run->s.regs.gprs[11] = 0xDEADBEEF;
 	run->s.regs.diag318 = 0x4B1D;
 	rv = _vcpu_run(vcpu);
-	TEST_ASSERT(rv == 0, "vcpu_run failed: %d\n", rv);
+	TEST_ASSERT(rv == 0, "vcpu_run failed: %d", rv);
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC);
 	TEST_ASSERT(run->s.regs.gprs[11] != 0xDEADBEEF,
 		    "r11 sync regs value incorrect 0x%llx.",
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index 075b80dbe237..40337f566eeb 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -98,11 +98,11 @@ static void wait_for_vcpu(void)
 	struct timespec ts;
 
 	TEST_ASSERT(!clock_gettime(CLOCK_REALTIME, &ts),
-		    "clock_gettime() failed: %d\n", errno);
+		    "clock_gettime() failed: %d", errno);
 
 	ts.tv_sec += 2;
 	TEST_ASSERT(!sem_timedwait(&vcpu_ready, &ts),
-		    "sem_timedwait() failed: %d\n", errno);
+		    "sem_timedwait() failed: %d", errno);
 
 	/* Wait for the vCPU thread to reenter the guest. */
 	usleep(100000);
@@ -302,7 +302,7 @@ static void test_delete_memory_region(void)
 	if (run->exit_reason == KVM_EXIT_INTERNAL_ERROR)
 		TEST_ASSERT(regs.rip >= final_rip_start &&
 			    regs.rip < final_rip_end,
-			    "Bad rip, expected 0x%lx - 0x%lx, got 0x%llx\n",
+			    "Bad rip, expected 0x%lx - 0x%lx, got 0x%llx",
 			    final_rip_start, final_rip_end, regs.rip);
 
 	kvm_vm_free(vm);
diff --git a/tools/testing/selftests/kvm/system_counter_offset_test.c b/tools/testing/selftests/kvm/system_counter_offset_test.c
index 7f5b330b6a1b..513d421a9bff 100644
--- a/tools/testing/selftests/kvm/system_counter_offset_test.c
+++ b/tools/testing/selftests/kvm/system_counter_offset_test.c
@@ -108,7 +108,7 @@ static void enter_guest(struct kvm_vcpu *vcpu)
 			handle_abort(&uc);
 			return;
 		default:
-			TEST_ASSERT(0, "unhandled ucall %ld\n",
+			TEST_ASSERT(0, "unhandled ucall %ld",
 				    get_ucall(vcpu, &uc));
 		}
 	}
diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c
index 11329e5ff945..eae521f050e0 100644
--- a/tools/testing/selftests/kvm/x86_64/amx_test.c
+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c
@@ -221,7 +221,7 @@ int main(int argc, char *argv[])
 	vm_vaddr_t amx_cfg, tiledata, xstate;
 	struct ucall uc;
 	u32 amx_offset;
-	int stage, ret;
+	int ret;
 
 	/*
 	 * Note, all off-by-default features must be enabled before anything
@@ -263,7 +263,7 @@ int main(int argc, char *argv[])
 	memset(addr_gva2hva(vm, xstate), 0, PAGE_SIZE * DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE));
 	vcpu_args_set(vcpu, 3, amx_cfg, tiledata, xstate);
 
-	for (stage = 1; ; stage++) {
+	for (;;) {
 		vcpu_run(vcpu);
 		TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
 
@@ -296,7 +296,7 @@ int main(int argc, char *argv[])
 				void *tiles_data = (void *)addr_gva2hva(vm, tiledata);
 				/* Only check TMM0 register, 1 tile */
 				ret = memcmp(amx_start, tiles_data, TILE_SIZE);
-				TEST_ASSERT(ret == 0, "memcmp failed, ret=%d\n", ret);
+				TEST_ASSERT(ret == 0, "memcmp failed, ret=%d", ret);
 				kvm_x86_state_cleanup(state);
 				break;
 			case 9:
diff --git a/tools/testing/selftests/kvm/x86_64/cpuid_test.c b/tools/testing/selftests/kvm/x86_64/cpuid_test.c
index 3b34d8156d1c..8c579ce714e9 100644
--- a/tools/testing/selftests/kvm/x86_64/cpuid_test.c
+++ b/tools/testing/selftests/kvm/x86_64/cpuid_test.c
@@ -84,7 +84,7 @@ static void compare_cpuids(const struct kvm_cpuid2 *cpuid1,
 
 		TEST_ASSERT(e1->function == e2->function &&
 			    e1->index == e2->index && e1->flags == e2->flags,
-			    "CPUID entries[%d] mismtach: 0x%x.%d.%x vs. 0x%x.%d.%x\n",
+			    "CPUID entries[%d] mismtach: 0x%x.%d.%x vs. 0x%x.%d.%x",
 			    i, e1->function, e1->index, e1->flags,
 			    e2->function, e2->index, e2->flags);
 
@@ -170,7 +170,7 @@ static void test_get_cpuid2(struct kvm_vcpu *vcpu)
 
 	vcpu_ioctl(vcpu, KVM_GET_CPUID2, cpuid);
 	TEST_ASSERT(cpuid->nent == vcpu->cpuid->nent,
-		    "KVM didn't update nent on success, wanted %u, got %u\n",
+		    "KVM didn't update nent on success, wanted %u, got %u",
 		    vcpu->cpuid->nent, cpuid->nent);
 
 	for (i = 0; i < vcpu->cpuid->nent; i++) {
diff --git a/tools/testing/selftests/kvm/x86_64/dirty_log_page_splitting_test.c b/tools/testing/selftests/kvm/x86_64/dirty_log_page_splitting_test.c
index 634c6bfcd572..ee3b384b991c 100644
--- a/tools/testing/selftests/kvm/x86_64/dirty_log_page_splitting_test.c
+++ b/tools/testing/selftests/kvm/x86_64/dirty_log_page_splitting_test.c
@@ -92,7 +92,6 @@ static void run_test(enum vm_guest_mode mode, void *unused)
 	uint64_t host_num_pages;
 	uint64_t pages_per_slot;
 	int i;
-	uint64_t total_4k_pages;
 	struct kvm_page_stats stats_populated;
 	struct kvm_page_stats stats_dirty_logging_enabled;
 	struct kvm_page_stats stats_dirty_pass[ITERATIONS];
@@ -107,6 +106,9 @@ static void run_test(enum vm_guest_mode mode, void *unused)
 	guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);
 	host_num_pages = vm_num_host_pages(mode, guest_num_pages);
 	pages_per_slot = host_num_pages / SLOTS;
+	TEST_ASSERT_EQ(host_num_pages, pages_per_slot * SLOTS);
+	TEST_ASSERT(!(host_num_pages % 512),
+		    "Number of pages, '%lu' not a multiple of 2MiB", host_num_pages);
 
 	bitmaps = memstress_alloc_bitmaps(SLOTS, pages_per_slot);
 
@@ -165,10 +167,8 @@ static void run_test(enum vm_guest_mode mode, void *unused)
 	memstress_free_bitmaps(bitmaps, SLOTS);
 	memstress_destroy_vm(vm);
 
-	/* Make assertions about the page counts. */
-	total_4k_pages = stats_populated.pages_4k;
-	total_4k_pages += stats_populated.pages_2m * 512;
-	total_4k_pages += stats_populated.pages_1g * 512 * 512;
+	TEST_ASSERT_EQ((stats_populated.pages_2m * 512 +
+			stats_populated.pages_1g * 512 * 512), host_num_pages);
 
 	/*
 	 * Check that all huge pages were split. Since large pages can only
@@ -180,19 +180,22 @@ static void run_test(enum vm_guest_mode mode, void *unused)
 	 */
 	if (dirty_log_manual_caps) {
 		TEST_ASSERT_EQ(stats_clear_pass[0].hugepages, 0);
-		TEST_ASSERT_EQ(stats_clear_pass[0].pages_4k, total_4k_pages);
+		TEST_ASSERT(stats_clear_pass[0].pages_4k >= host_num_pages,
+			    "Expected at least '%lu' 4KiB pages, found only '%lu'",
+			    host_num_pages, stats_clear_pass[0].pages_4k);
 		TEST_ASSERT_EQ(stats_dirty_logging_enabled.hugepages, stats_populated.hugepages);
 	} else {
 		TEST_ASSERT_EQ(stats_dirty_logging_enabled.hugepages, 0);
-		TEST_ASSERT_EQ(stats_dirty_logging_enabled.pages_4k, total_4k_pages);
+		TEST_ASSERT(stats_dirty_logging_enabled.pages_4k >= host_num_pages,
+			    "Expected at least '%lu' 4KiB pages, found only '%lu'",
+			    host_num_pages, stats_dirty_logging_enabled.pages_4k);
 	}
 
 	/*
 	 * Once dirty logging is disabled and the vCPUs have touched all their
-	 * memory again, the page counts should be the same as they were
+	 * memory again, the hugepage counts should be the same as they were
 	 * right after initial population of memory.
 	 */
-	TEST_ASSERT_EQ(stats_populated.pages_4k, stats_repopulated.pages_4k);
 	TEST_ASSERT_EQ(stats_populated.pages_2m, stats_repopulated.pages_2m);
 	TEST_ASSERT_EQ(stats_populated.pages_1g, stats_repopulated.pages_1g);
 }
diff --git a/tools/testing/selftests/kvm/x86_64/flds_emulation.h b/tools/testing/selftests/kvm/x86_64/flds_emulation.h
index 0a1573d52882..37b1a9f52864 100644
--- a/tools/testing/selftests/kvm/x86_64/flds_emulation.h
+++ b/tools/testing/selftests/kvm/x86_64/flds_emulation.h
@@ -41,7 +41,7 @@ static inline void handle_flds_emulation_failure_exit(struct kvm_vcpu *vcpu)
 
 	insn_bytes = run->emulation_failure.insn_bytes;
 	TEST_ASSERT(insn_bytes[0] == 0xd9 && insn_bytes[1] == 0,
-		    "Expected 'flds [eax]', opcode '0xd9 0x00', got opcode 0x%02x 0x%02x\n",
+		    "Expected 'flds [eax]', opcode '0xd9 0x00', got opcode 0x%02x 0x%02x",
 		    insn_bytes[0], insn_bytes[1]);
 
 	vcpu_regs_get(vcpu, &regs);
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_clock.c b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c
index f5e1e98f04f9..e058bc676cd6 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_clock.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c
@@ -212,6 +212,7 @@ int main(void)
 	int stage;
 
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_TIME));
+	TEST_REQUIRE(sys_clocksource_is_based_on_tsc());
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
 
@@ -220,7 +221,7 @@ int main(void)
 	tsc_page_gva = vm_vaddr_alloc_page(vm);
 	memset(addr_gva2hva(vm, tsc_page_gva), 0x0, getpagesize());
 	TEST_ASSERT((addr_gva2gpa(vm, tsc_page_gva) & (getpagesize() - 1)) == 0,
-		"TSC page has to be page aligned\n");
+		"TSC page has to be page aligned");
 	vcpu_args_set(vcpu, 2, tsc_page_gva, addr_gva2gpa(vm, tsc_page_gva));
 
 	host_check_tsc_msr_rdtsc(vcpu);
@@ -237,7 +238,7 @@ int main(void)
 			break;
 		case UCALL_DONE:
 			/* Keep in sync with guest_main() */
-			TEST_ASSERT(stage == 11, "Testing ended prematurely, stage %d\n",
+			TEST_ASSERT(stage == 11, "Testing ended prematurely, stage %d",
 				    stage);
 			goto out;
 		default:
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_features.c b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
index 4f4193fc74ff..b923a285e96f 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_features.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
@@ -454,7 +454,7 @@ static void guest_test_msrs_access(void)
 		case 44:
 			/* MSR is not available when CPUID feature bit is unset */
 			if (!has_invtsc)
-				continue;
+				goto next_stage;
 			msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
 			msr->write = false;
 			msr->fault_expected = true;
@@ -462,7 +462,7 @@ static void guest_test_msrs_access(void)
 		case 45:
 			/* MSR is vailable when CPUID feature bit is set */
 			if (!has_invtsc)
-				continue;
+				goto next_stage;
 			vcpu_set_cpuid_feature(vcpu, HV_ACCESS_TSC_INVARIANT);
 			msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
 			msr->write = false;
@@ -471,7 +471,7 @@ static void guest_test_msrs_access(void)
 		case 46:
 			/* Writing bits other than 0 is forbidden */
 			if (!has_invtsc)
-				continue;
+				goto next_stage;
 			msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
 			msr->write = true;
 			msr->write_val = 0xdeadbeef;
@@ -480,7 +480,7 @@ static void guest_test_msrs_access(void)
 		case 47:
 			/* Setting bit 0 enables the feature */
 			if (!has_invtsc)
-				continue;
+				goto next_stage;
 			msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
 			msr->write = true;
 			msr->write_val = 1;
@@ -513,6 +513,7 @@ static void guest_test_msrs_access(void)
 			return;
 		}
 
+next_stage:
 		stage++;
 		kvm_vm_free(vm);
 	}
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c b/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
index 65e5f4c05068..f1617762c22f 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
@@ -289,7 +289,7 @@ int main(int argc, char *argv[])
 		switch (get_ucall(vcpu[0], &uc)) {
 		case UCALL_SYNC:
 			TEST_ASSERT(uc.args[1] == stage,
-				    "Unexpected stage: %ld (%d expected)\n",
+				    "Unexpected stage: %ld (%d expected)",
 				    uc.args[1], stage);
 			break;
 		case UCALL_DONE:
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c b/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c
index c4443f71f8dd..05b56095cf76 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c
@@ -658,7 +658,7 @@ int main(int argc, char *argv[])
 		switch (get_ucall(vcpu[0], &uc)) {
 		case UCALL_SYNC:
 			TEST_ASSERT(uc.args[1] == stage,
-				    "Unexpected stage: %ld (%d expected)\n",
+				    "Unexpected stage: %ld (%d expected)",
 				    uc.args[1], stage);
 			break;
 		case UCALL_ABORT:
diff --git a/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c b/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c
index 1778704360a6..5bc12222d87a 100644
--- a/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c
@@ -92,7 +92,7 @@ static void setup_clock(struct kvm_vm *vm, struct test_case *test_case)
 				break;
 		} while (errno == EINTR);
 
-		TEST_ASSERT(!r, "clock_gettime() failed: %d\n", r);
+		TEST_ASSERT(!r, "clock_gettime() failed: %d", r);
 
 		data.realtime = ts.tv_sec * NSEC_PER_SEC;
 		data.realtime += ts.tv_nsec;
@@ -127,47 +127,11 @@ static void enter_guest(struct kvm_vcpu *vcpu)
 			handle_abort(&uc);
 			return;
 		default:
-			TEST_ASSERT(0, "unhandled ucall: %ld\n", uc.cmd);
+			TEST_ASSERT(0, "unhandled ucall: %ld", uc.cmd);
 		}
 	}
 }
 
-#define CLOCKSOURCE_PATH "/sys/devices/system/clocksource/clocksource0/current_clocksource"
-
-static void check_clocksource(void)
-{
-	char *clk_name;
-	struct stat st;
-	FILE *fp;
-
-	fp = fopen(CLOCKSOURCE_PATH, "r");
-	if (!fp) {
-		pr_info("failed to open clocksource file: %d; assuming TSC.\n",
-			errno);
-		return;
-	}
-
-	if (fstat(fileno(fp), &st)) {
-		pr_info("failed to stat clocksource file: %d; assuming TSC.\n",
-			errno);
-		goto out;
-	}
-
-	clk_name = malloc(st.st_size);
-	TEST_ASSERT(clk_name, "failed to allocate buffer to read file\n");
-
-	if (!fgets(clk_name, st.st_size, fp)) {
-		pr_info("failed to read clocksource file: %d; assuming TSC.\n",
-			ferror(fp));
-		goto out;
-	}
-
-	TEST_ASSERT(!strncmp(clk_name, "tsc\n", st.st_size),
-		    "clocksource not supported: %s", clk_name);
-out:
-	fclose(fp);
-}
-
 int main(void)
 {
 	struct kvm_vcpu *vcpu;
@@ -179,7 +143,7 @@ int main(void)
 	flags = kvm_check_cap(KVM_CAP_ADJUST_CLOCK);
 	TEST_REQUIRE(flags & KVM_CLOCK_REALTIME);
 
-	check_clocksource();
+	TEST_REQUIRE(sys_clocksource_is_based_on_tsc());
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
 
diff --git a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
index 83e25bccc139..17bbb96fc4df 100644
--- a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
+++ b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
@@ -257,9 +257,9 @@ int main(int argc, char **argv)
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_VM_DISABLE_NX_HUGE_PAGES));
 
 	__TEST_REQUIRE(token == MAGIC_TOKEN,
-		       "This test must be run with the magic token %d.\n"
-		       "This is done by nx_huge_pages_test.sh, which\n"
-		       "also handles environment setup for the test.", MAGIC_TOKEN);
+		       "This test must be run with the magic token via '-t %d'.\n"
+		       "Running via nx_huge_pages_test.sh, which also handles "
+		       "environment setup, is strongly recommended.", MAGIC_TOKEN);
 
 	run_test(reclaim_period_ms, false, reboot_permissions);
 	run_test(reclaim_period_ms, true, reboot_permissions);
diff --git a/tools/testing/selftests/kvm/x86_64/platform_info_test.c b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
index c9a07963d68a..87011965dc41 100644
--- a/tools/testing/selftests/kvm/x86_64/platform_info_test.c
+++ b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
@@ -44,7 +44,7 @@ static void test_msr_platform_info_enabled(struct kvm_vcpu *vcpu)
 
 	get_ucall(vcpu, &uc);
 	TEST_ASSERT(uc.cmd == UCALL_SYNC,
-			"Received ucall other than UCALL_SYNC: %lu\n", uc.cmd);
+			"Received ucall other than UCALL_SYNC: %lu", uc.cmd);
 	TEST_ASSERT((uc.args[1] & MSR_PLATFORM_INFO_MAX_TURBO_RATIO) ==
 		MSR_PLATFORM_INFO_MAX_TURBO_RATIO,
 		"Expected MSR_PLATFORM_INFO to have max turbo ratio mask: %i.",
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index 283cc55597a4..a3bd54b925ab 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -866,7 +866,7 @@ static void __test_fixed_counter_bitmap(struct kvm_vcpu *vcpu, uint8_t idx,
 	 * userspace doesn't set any pmu filter.
 	 */
 	count = run_vcpu_to_sync(vcpu);
-	TEST_ASSERT(count, "Unexpected count value: %ld\n", count);
+	TEST_ASSERT(count, "Unexpected count value: %ld", count);
 
 	for (i = 0; i < BIT(nr_fixed_counters); i++) {
 		bitmap = BIT(i);
diff --git a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
index c7ef97561038..a49828adf294 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
@@ -91,7 +91,7 @@ static void sev_migrate_from(struct kvm_vm *dst, struct kvm_vm *src)
 	int ret;
 
 	ret = __sev_migrate_from(dst, src);
-	TEST_ASSERT(!ret, "Migration failed, ret: %d, errno: %d\n", ret, errno);
+	TEST_ASSERT(!ret, "Migration failed, ret: %d, errno: %d", ret, errno);
 }
 
 static void test_sev_migrate_from(bool es)
@@ -113,7 +113,7 @@ static void test_sev_migrate_from(bool es)
 	/* Migrate the guest back to the original VM. */
 	ret = __sev_migrate_from(src_vm, dst_vms[NR_MIGRATE_TEST_VMS - 1]);
 	TEST_ASSERT(ret == -1 && errno == EIO,
-		    "VM that was migrated from should be dead. ret %d, errno: %d\n", ret,
+		    "VM that was migrated from should be dead. ret %d, errno: %d", ret,
 		    errno);
 
 	kvm_vm_free(src_vm);
@@ -172,7 +172,7 @@ static void test_sev_migrate_parameters(void)
 	vm_no_sev = aux_vm_create(true);
 	ret = __sev_migrate_from(vm_no_vcpu, vm_no_sev);
 	TEST_ASSERT(ret == -1 && errno == EINVAL,
-		    "Migrations require SEV enabled. ret %d, errno: %d\n", ret,
+		    "Migrations require SEV enabled. ret %d, errno: %d", ret,
 		    errno);
 
 	if (!have_sev_es)
@@ -187,25 +187,25 @@ static void test_sev_migrate_parameters(void)
 	ret = __sev_migrate_from(sev_vm, sev_es_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"Should not be able migrate to SEV enabled VM. ret: %d, errno: %d\n",
+		"Should not be able migrate to SEV enabled VM. ret: %d, errno: %d",
 		ret, errno);
 
 	ret = __sev_migrate_from(sev_es_vm, sev_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"Should not be able migrate to SEV-ES enabled VM. ret: %d, errno: %d\n",
+		"Should not be able migrate to SEV-ES enabled VM. ret: %d, errno: %d",
 		ret, errno);
 
 	ret = __sev_migrate_from(vm_no_vcpu, sev_es_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"SEV-ES migrations require same number of vCPUS. ret: %d, errno: %d\n",
+		"SEV-ES migrations require same number of vCPUS. ret: %d, errno: %d",
 		ret, errno);
 
 	ret = __sev_migrate_from(vm_no_vcpu, sev_es_vm_no_vmsa);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"SEV-ES migrations require UPDATE_VMSA. ret %d, errno: %d\n",
+		"SEV-ES migrations require UPDATE_VMSA. ret %d, errno: %d",
 		ret, errno);
 
 	kvm_vm_free(sev_vm);
@@ -227,7 +227,7 @@ static void sev_mirror_create(struct kvm_vm *dst, struct kvm_vm *src)
 	int ret;
 
 	ret = __sev_mirror_create(dst, src);
-	TEST_ASSERT(!ret, "Copying context failed, ret: %d, errno: %d\n", ret, errno);
+	TEST_ASSERT(!ret, "Copying context failed, ret: %d, errno: %d", ret, errno);
 }
 
 static void verify_mirror_allowed_cmds(int vm_fd)
@@ -259,7 +259,7 @@ static void verify_mirror_allowed_cmds(int vm_fd)
 		ret = __sev_ioctl(vm_fd, cmd_id, NULL, &fw_error);
 		TEST_ASSERT(
 			ret == -1 && errno == EINVAL,
-			"Should not be able call command: %d. ret: %d, errno: %d\n",
+			"Should not be able call command: %d. ret: %d, errno: %d",
 			cmd_id, ret, errno);
 	}
 
@@ -301,18 +301,18 @@ static void test_sev_mirror_parameters(void)
 	ret = __sev_mirror_create(sev_vm, sev_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"Should not be able copy context to self. ret: %d, errno: %d\n",
+		"Should not be able copy context to self. ret: %d, errno: %d",
 		ret, errno);
 
 	ret = __sev_mirror_create(vm_no_vcpu, vm_with_vcpu);
 	TEST_ASSERT(ret == -1 && errno == EINVAL,
-		    "Copy context requires SEV enabled. ret %d, errno: %d\n", ret,
+		    "Copy context requires SEV enabled. ret %d, errno: %d", ret,
 		    errno);
 
 	ret = __sev_mirror_create(vm_with_vcpu, sev_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"SEV copy context requires no vCPUS on the destination. ret: %d, errno: %d\n",
+		"SEV copy context requires no vCPUS on the destination. ret: %d, errno: %d",
 		ret, errno);
 
 	if (!have_sev_es)
@@ -322,13 +322,13 @@ static void test_sev_mirror_parameters(void)
 	ret = __sev_mirror_create(sev_vm, sev_es_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"Should not be able copy context to SEV enabled VM. ret: %d, errno: %d\n",
+		"Should not be able copy context to SEV enabled VM. ret: %d, errno: %d",
 		ret, errno);
 
 	ret = __sev_mirror_create(sev_es_vm, sev_vm);
 	TEST_ASSERT(
 		ret == -1 && errno == EINVAL,
-		"Should not be able copy context to SEV-ES enabled VM. ret: %d, errno: %d\n",
+		"Should not be able copy context to SEV-ES enabled VM. ret: %d, errno: %d",
 		ret, errno);
 
 	kvm_vm_free(sev_es_vm);
diff --git a/tools/testing/selftests/kvm/x86_64/smaller_maxphyaddr_emulation_test.c b/tools/testing/selftests/kvm/x86_64/smaller_maxphyaddr_emulation_test.c
index 06edf00a97d6..1a46dd7bb391 100644
--- a/tools/testing/selftests/kvm/x86_64/smaller_maxphyaddr_emulation_test.c
+++ b/tools/testing/selftests/kvm/x86_64/smaller_maxphyaddr_emulation_test.c
@@ -74,7 +74,7 @@ int main(int argc, char *argv[])
 				    MEM_REGION_SIZE / PAGE_SIZE, 0);
 	gpa = vm_phy_pages_alloc(vm, MEM_REGION_SIZE / PAGE_SIZE,
 				 MEM_REGION_GPA, MEM_REGION_SLOT);
-	TEST_ASSERT(gpa == MEM_REGION_GPA, "Failed vm_phy_pages_alloc\n");
+	TEST_ASSERT(gpa == MEM_REGION_GPA, "Failed vm_phy_pages_alloc");
 	virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1);
 	hva = addr_gpa2hva(vm, MEM_REGION_GPA);
 	memset(hva, 0, PAGE_SIZE);
@@ -102,7 +102,7 @@ int main(int argc, char *argv[])
 	case UCALL_DONE:
 		break;
 	default:
-		TEST_FAIL("Unrecognized ucall: %lu\n", uc.cmd);
+		TEST_FAIL("Unrecognized ucall: %lu", uc.cmd);
 	}
 
 	kvm_vm_free(vm);
diff --git a/tools/testing/selftests/kvm/x86_64/sync_regs_test.c b/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
index 00965ba33f73..a91b5b145fa3 100644
--- a/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
@@ -46,7 +46,7 @@ static void compare_regs(struct kvm_regs *left, struct kvm_regs *right)
 #define REG_COMPARE(reg) \
 	TEST_ASSERT(left->reg == right->reg, \
 		    "Register " #reg \
-		    " values did not match: 0x%llx, 0x%llx\n", \
+		    " values did not match: 0x%llx, 0x%llx", \
 		    left->reg, right->reg)
 	REG_COMPARE(rax);
 	REG_COMPARE(rbx);
@@ -230,14 +230,14 @@ int main(int argc, char *argv[])
 	run->kvm_valid_regs = INVALID_SYNC_FIELD;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_valid_regs = 0;
 
 	run->kvm_valid_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_valid_regs = 0;
 
@@ -245,14 +245,14 @@ int main(int argc, char *argv[])
 	run->kvm_dirty_regs = INVALID_SYNC_FIELD;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_dirty_regs = 0;
 
 	run->kvm_dirty_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vcpu);
 	TEST_ASSERT(rv < 0 && errno == EINVAL,
-		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d",
 		    rv);
 	run->kvm_dirty_regs = 0;
 
diff --git a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
index 0ed32ec903d0..dcbb3c29fb8e 100644
--- a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
+++ b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
@@ -143,7 +143,7 @@ static void run_vcpu_expect_gp(struct kvm_vcpu *vcpu)
 
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
 	TEST_ASSERT(get_ucall(vcpu, &uc) == UCALL_SYNC,
-		    "Expect UCALL_SYNC\n");
+		    "Expect UCALL_SYNC");
 	TEST_ASSERT(uc.args[1] == SYNC_GP, "#GP is expected.");
 	printf("vCPU received GP in guest.\n");
 }
@@ -188,7 +188,7 @@ static void *run_ucna_injection(void *arg)
 
 	TEST_ASSERT_KVM_EXIT_REASON(params->vcpu, KVM_EXIT_IO);
 	TEST_ASSERT(get_ucall(params->vcpu, &uc) == UCALL_SYNC,
-		    "Expect UCALL_SYNC\n");
+		    "Expect UCALL_SYNC");
 	TEST_ASSERT(uc.args[1] == SYNC_FIRST_UCNA, "Injecting first UCNA.");
 
 	printf("Injecting first UCNA at %#x.\n", FIRST_UCNA_ADDR);
@@ -198,7 +198,7 @@ static void *run_ucna_injection(void *arg)
 
 	TEST_ASSERT_KVM_EXIT_REASON(params->vcpu, KVM_EXIT_IO);
 	TEST_ASSERT(get_ucall(params->vcpu, &uc) == UCALL_SYNC,
-		    "Expect UCALL_SYNC\n");
+		    "Expect UCALL_SYNC");
 	TEST_ASSERT(uc.args[1] == SYNC_SECOND_UCNA, "Injecting second UCNA.");
 
 	printf("Injecting second UCNA at %#x.\n", SECOND_UCNA_ADDR);
@@ -208,7 +208,7 @@ static void *run_ucna_injection(void *arg)
 
 	TEST_ASSERT_KVM_EXIT_REASON(params->vcpu, KVM_EXIT_IO);
 	if (get_ucall(params->vcpu, &uc) == UCALL_ABORT) {
-		TEST_ASSERT(false, "vCPU assertion failure: %s.\n",
+		TEST_ASSERT(false, "vCPU assertion failure: %s.",
 			    (const char *)uc.args[0]);
 	}
 
diff --git a/tools/testing/selftests/kvm/x86_64/userspace_io_test.c b/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
index 255c50b0dc32..9481cbcf284f 100644
--- a/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
+++ b/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
@@ -71,7 +71,7 @@ int main(int argc, char *argv[])
 			break;
 
 		TEST_ASSERT(run->io.port == 0x80,
-			    "Expected I/O at port 0x80, got port 0x%x\n", run->io.port);
+			    "Expected I/O at port 0x80, got port 0x%x", run->io.port);
 
 		/*
 		 * Modify the rep string count in RCX: 2 => 1 and 3 => 8192.
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_apic_access_test.c b/tools/testing/selftests/kvm/x86_64/vmx_apic_access_test.c
index 2bed5fb3a0d6..a81a24761aac 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_apic_access_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_apic_access_test.c
@@ -99,7 +99,7 @@ int main(int argc, char *argv[])
 			TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_INTERNAL_ERROR);
 			TEST_ASSERT(run->internal.suberror ==
 				    KVM_INTERNAL_ERROR_EMULATION,
-				    "Got internal suberror other than KVM_INTERNAL_ERROR_EMULATION: %u\n",
+				    "Got internal suberror other than KVM_INTERNAL_ERROR_EMULATION: %u",
 				    run->internal.suberror);
 			break;
 		}
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_dirty_log_test.c b/tools/testing/selftests/kvm/x86_64/vmx_dirty_log_test.c
index e4ad5fef52ff..7f6f5f23fb9b 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_dirty_log_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_dirty_log_test.c
@@ -128,17 +128,17 @@ int main(int argc, char *argv[])
 			 */
 			kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap);
 			if (uc.args[1]) {
-				TEST_ASSERT(test_bit(0, bmap), "Page 0 incorrectly reported clean\n");
-				TEST_ASSERT(host_test_mem[0] == 1, "Page 0 not written by guest\n");
+				TEST_ASSERT(test_bit(0, bmap), "Page 0 incorrectly reported clean");
+				TEST_ASSERT(host_test_mem[0] == 1, "Page 0 not written by guest");
 			} else {
-				TEST_ASSERT(!test_bit(0, bmap), "Page 0 incorrectly reported dirty\n");
-				TEST_ASSERT(host_test_mem[0] == 0xaaaaaaaaaaaaaaaaULL, "Page 0 written by guest\n");
+				TEST_ASSERT(!test_bit(0, bmap), "Page 0 incorrectly reported dirty");
+				TEST_ASSERT(host_test_mem[0] == 0xaaaaaaaaaaaaaaaaULL, "Page 0 written by guest");
 			}
 
-			TEST_ASSERT(!test_bit(1, bmap), "Page 1 incorrectly reported dirty\n");
-			TEST_ASSERT(host_test_mem[4096 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 1 written by guest\n");
-			TEST_ASSERT(!test_bit(2, bmap), "Page 2 incorrectly reported dirty\n");
-			TEST_ASSERT(host_test_mem[8192 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 2 written by guest\n");
+			TEST_ASSERT(!test_bit(1, bmap), "Page 1 incorrectly reported dirty");
+			TEST_ASSERT(host_test_mem[4096 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 1 written by guest");
+			TEST_ASSERT(!test_bit(2, bmap), "Page 2 incorrectly reported dirty");
+			TEST_ASSERT(host_test_mem[8192 / 8] == 0xaaaaaaaaaaaaaaaaULL, "Page 2 written by guest");
 			break;
 		case UCALL_DONE:
 			done = true;
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
index a9b827c69f32..fad3634fd9eb 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_exception_with_invalid_guest_state.c
@@ -28,7 +28,7 @@ static void __run_vcpu_with_invalid_state(struct kvm_vcpu *vcpu)
 
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_INTERNAL_ERROR);
 	TEST_ASSERT(run->emulation_failure.suberror == KVM_INTERNAL_ERROR_EMULATION,
-		    "Expected emulation failure, got %d\n",
+		    "Expected emulation failure, got %d",
 		    run->emulation_failure.suberror);
 }
 
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c b/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
index e710b6e7fb38..1759fa5cb3f2 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
@@ -116,23 +116,6 @@ static void l1_guest_code(struct vmx_pages *vmx_pages)
 	GUEST_DONE();
 }
 
-static bool system_has_stable_tsc(void)
-{
-	bool tsc_is_stable;
-	FILE *fp;
-	char buf[4];
-
-	fp = fopen("/sys/devices/system/clocksource/clocksource0/current_clocksource", "r");
-	if (fp == NULL)
-		return false;
-
-	tsc_is_stable = fgets(buf, sizeof(buf), fp) &&
-			!strncmp(buf, "tsc", sizeof(buf));
-
-	fclose(fp);
-	return tsc_is_stable;
-}
-
 int main(int argc, char *argv[])
 {
 	struct kvm_vcpu *vcpu;
@@ -148,7 +131,7 @@ int main(int argc, char *argv[])
 
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_TSC_CONTROL));
-	TEST_REQUIRE(system_has_stable_tsc());
+	TEST_REQUIRE(sys_clocksource_is_based_on_tsc());
 
 	/*
 	 * We set L1's scale factor to be a random number from 2 to 10.
diff --git a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
index 67ac2a3292ef..725c206ba0b9 100644
--- a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
@@ -216,7 +216,7 @@ static void *vcpu_thread(void *arg)
 			    "Halting vCPU halted %lu times, woke %lu times, received %lu IPIs.\n"
 			    "Halter TPR=%#x PPR=%#x LVR=%#x\n"
 			    "Migrations attempted: %lu\n"
-			    "Migrations completed: %lu\n",
+			    "Migrations completed: %lu",
 			    vcpu->id, (const char *)uc.args[0],
 			    params->data->ipis_sent, params->data->hlt_count,
 			    params->data->wake_count,
@@ -288,7 +288,7 @@ void do_migrations(struct test_data_page *data, int run_secs, int delay_usecs,
 	}
 
 	TEST_ASSERT(nodes > 1,
-		    "Did not find at least 2 numa nodes. Can't do migration\n");
+		    "Did not find at least 2 numa nodes. Can't do migration");
 
 	fprintf(stderr, "Migrating amongst %d nodes found\n", nodes);
 
@@ -347,7 +347,7 @@ void do_migrations(struct test_data_page *data, int run_secs, int delay_usecs,
 				    wake_count != data->wake_count,
 				    "IPI, HLT and wake count have not increased "
 				    "in the last %lu seconds. "
-				    "HLTer is likely hung.\n", interval_secs);
+				    "HLTer is likely hung.", interval_secs);
 
 			ipis_sent = data->ipis_sent;
 			hlt_count = data->hlt_count;
@@ -381,7 +381,7 @@ void get_cmdline_args(int argc, char *argv[], int *run_secs,
 				    "-m adds calls to migrate_pages while vCPUs are running."
 				    " Default is no migrations.\n"
 				    "-d <delay microseconds> - delay between migrate_pages() calls."
-				    " Default is %d microseconds.\n",
+				    " Default is %d microseconds.",
 				    DEFAULT_RUN_SECS, DEFAULT_DELAY_USECS);
 		}
 	}
diff --git a/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c b/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c
index dc6217440db3..25a0b0db5c3c 100644
--- a/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c
@@ -116,7 +116,7 @@ int main(int argc, char *argv[])
 		vcpu_run(vcpu);
 
 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
-			    "Unexpected exit reason: %u (%s),\n",
+			    "Unexpected exit reason: %u (%s),",
 			    run->exit_reason,
 			    exit_reason_str(run->exit_reason));
 
diff --git a/tools/testing/selftests/kvm/x86_64/xss_msr_test.c b/tools/testing/selftests/kvm/x86_64/xss_msr_test.c
index e0ddf47362e7..167c97abff1b 100644
--- a/tools/testing/selftests/kvm/x86_64/xss_msr_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xss_msr_test.c
@@ -29,7 +29,7 @@ int main(int argc, char *argv[])
 
 	xss_val = vcpu_get_msr(vcpu, MSR_IA32_XSS);
 	TEST_ASSERT(xss_val == 0,
-		    "MSR_IA32_XSS should be initialized to zero\n");
+		    "MSR_IA32_XSS should be initialized to zero");
 
 	vcpu_set_msr(vcpu, MSR_IA32_XSS, xss_val);