Commit bf1e15a8 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: selftests: Always run vCPU thread with blocked SIG_IPI 



The main thread could start to send SIG_IPI at any time, even before signal
blocked on vcpu thread.  Therefore, start the vcpu thread with the signal
blocked.

Without this patch, on very busy cores the dirty_log_test could fail directly
on receiving a SIGUSR1 without a handler (when vcpu runs far slower than main).

Reported-by: default avatarPeter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 016ff1a4

tools/testing/selftests/kvm/dirty_log_test.c

+7 −2
Original line number Diff line number Diff line
@@ -527,9 +527,8 @@ static void *vcpu_worker(void *data) 
	 */

	sigmask->len = 8;

	pthread_sigmask(0, NULL, sigset);

	sigdelset(sigset, SIG_IPI);

	vcpu_ioctl(vm, VCPU_ID, KVM_SET_SIGNAL_MASK, sigmask);

	sigaddset(sigset, SIG_IPI);

	pthread_sigmask(SIG_BLOCK, sigset, NULL);



	sigemptyset(sigset);

	sigaddset(sigset, SIG_IPI);
@@ -858,6 +857,7 @@ int main(int argc, char *argv[]) 
		.interval = TEST_HOST_LOOP_INTERVAL,

	};

	int opt, i;

	sigset_t sigset;



	sem_init(&sem_vcpu_stop, 0, 0);

	sem_init(&sem_vcpu_cont, 0, 0);
@@ -916,6 +916,11 @@ int main(int argc, char *argv[]) 


	srandom(time(0));



	/* Ensure that vCPU threads start with SIG_IPI blocked.  */

	sigemptyset(&sigset);

	sigaddset(&sigset, SIG_IPI);

	pthread_sigmask(SIG_BLOCK, &sigset, NULL);



	if (host_log_mode_option == LOG_MODE_ALL) {

		/* Run each log mode */

		for (i = 0; i < LOG_MODE_NUM; i++) {