KVM: selftests: Drop unreachable, dead code from hardware disable test

Drop all of the code that is unreachable in the hardware disable test, as
it adds a lot of noise that makes the test seem far more complicated than
it actually is.

Link: https://patch.msgid.link/20260731195612.2697986-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 14 insertions, 27 deletions

diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c
index fcc06c602fca..de8e63da7b58 100644
--- a/tools/testing/selftests/kvm/hardware_disable_test.c
+++ b/tools/testing/selftests/kvm/hardware_disable_test.c
@@ -15,6 +15,7 @@
 #include <test_util.h>
 
 #include "kvm_util.h"
+#include "ucall_common.h"
 
 #define VCPU_NUM 4
 #define SLEEPING_THREAD_NUM (1 << 4)
@@ -28,7 +29,7 @@ static void guest_code(void)
 {
 	for (;;)
 		;  /* Some busy work */
-	printf("Should not be reached.\n");
+	GUEST_ASSERT(0);
 }
 
 static void *run_vcpu(void *arg)
@@ -42,10 +43,8 @@ static void *run_vcpu(void *arg)
 
 	vcpu_run(vcpu);
 
-	TEST_ASSERT(false, "%s: exited with reason %d: %s",
-		    __func__, run->exit_reason,
-		    exit_reason_str(run->exit_reason));
-	pthread_exit(NULL);
+	TEST_FAIL("vCPU%d exited with reason %d: %s",
+		  vcpu->id, run->exit_reason, exit_reason_str(run->exit_reason));
 }
 
 static void *sleeping_thread(void *arg)
@@ -56,12 +55,11 @@ static void *sleeping_thread(void *arg)
 	kvm_sched_setaffinity(0, sizeof(cpu_set_t), &threads_cpu_set);
 #endif
 
-	while (true) {
+	while (1) {
 		fd = open("/dev/null", O_RDWR);
 		close(fd);
 	}
-	TEST_ASSERT(false, "%s: exited", __func__);
-	pthread_exit(NULL);
+	TEST_FAIL("%s: exited", __func__);
 }
 
 static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
@@ -73,22 +71,12 @@ static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
 	TEST_ASSERT(r == 0, "%s: failed to create thread", __func__);
 }
 
-static inline void check_join(pthread_t thread, void **retval)
-{
-	int r;
-
-	r = pthread_join(thread, retval);
-	TEST_ASSERT(r == 0, "%s: failed to join thread", __func__);
-}
-
 static void run_test(u32 run)
 {
 	struct kvm_vcpu *vcpu;
 	pthread_attr_t attr;
 	struct kvm_vm *vm;
-	pthread_t threads[VCPU_NUM];
-	pthread_t throw_away;
-	void *b;
+	pthread_t thread;
 	u32 i, j;
 
 	TEST_ASSERT_EQ(pthread_attr_init(&attr), 0);
@@ -102,19 +90,18 @@ static void run_test(u32 run)
 	for (i = 0; i < VCPU_NUM; ++i) {
 		vcpu = vm_vcpu_add(vm, i, guest_code);
 
-		check_create_thread(&threads[i], &attr, run_vcpu, vcpu);
+		check_create_thread(&thread, &attr, run_vcpu, vcpu);
 
-		for (j = 0; j < SLEEPING_THREAD_NUM; ++j) {
-			check_create_thread(&throw_away, &attr, sleeping_thread,
+		for (j = 0; j < SLEEPING_THREAD_NUM; ++j)
+			check_create_thread(&thread, &attr, sleeping_thread,
 					    (void *)NULL);
-		}
 	}
 	pr_debug("%s: [%d] all threads launched\n", __func__, run);
 	sem_post(sem);
-	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", __func__, run);
+
+	/* Wait for the parent to SIGKILL this child. */
+	while (1)
+		pause();
 }
 
 void wait_for_child_setup(pid_t pid)