- Protect p_numthreads with the sched_lock.

- Protect p_singlethread with both the sched_lock and the proc lock.
- Protect p_suspcount with the proc lock.

1 files changed, 3 insertions, 0 deletions

diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index 187364b..8e16d3e 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -698,9 +698,11 @@ loop:
 			mtx_unlock(&Giant);
 			return (0);
 		}
+		mtx_lock_spin(&sched_lock);
 		if (P_SHOULDSTOP(p) && (p->p_suspcount == p->p_numthreads) &&
 		    ((p->p_flag & P_WAITED) == 0) &&
 		    (p->p_flag & P_TRACED || uap->options & WUNTRACED)) {
+			mtx_unlock_spin(&sched_lock);
 			p->p_flag |= P_WAITED;
 			sx_xunlock(&proctree_lock);
 			td->td_retval[0] = p->p_pid;
@@ -723,6 +725,7 @@ loop:
 			mtx_unlock(&Giant);
 			return (error);
 		}
+		mtx_unlock_spin(&sched_lock);
 		if (uap->options & WCONTINUED && (p->p_flag & P_CONTINUED)) {
 			sx_xunlock(&proctree_lock);
 			td->td_retval[0] = p->p_pid;