Index: sys/kern/kern_exec.c
===================================================================
--- sys/kern/kern_exec.c	(revision 230617)
+++ sys/kern/kern_exec.c	(working copy)
@@ -55,6 +55,7 @@
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/pioctl.h>
+#include <sys/ptrace.h>
 #include <sys/namei.h>
 #include <sys/resourcevar.h>
 #include <sys/sdt.h>
@@ -888,16 +889,22 @@
 	free(imgp->freepath, M_TEMP);
 
 	if (error == 0) {
+		if ((p->p_flag & (P_TRACED | P_FOLLOWEXEC)) == 
+		    (P_TRACED |	P_FOLLOWEXEC)) {
+			PROC_LOCK(p);
+			td->td_dbgflags |= TDB_EXEC;
+			PROC_UNLOCK(p);
+		}
+ 		/*
+ 		 * Stop the process here if its stop event mask has
+ 		 * the S_EXEC bit set.
+ 		 */
+ 		STOPEVENT(p, S_EXEC, 0);
+		PTRACESTOP_SC(p, td, S_PT_EXEC);
 		PROC_LOCK(p);
-		td->td_dbgflags |= TDB_EXEC;
+		td->td_dbgflags &= ~TDB_EXEC;
 		PROC_UNLOCK(p);
-
-		/*
-		 * Stop the process here if its stop event mask has
-		 * the S_EXEC bit set.
-		 */
-		STOPEVENT(p, S_EXEC, 0);
-		goto done2;
+ 		goto done2;
 	}
 
 exec_fail:
Index: sys/kern/sys_process.c
===================================================================
--- sys/kern/sys_process.c	(revision 230617)
+++ sys/kern/sys_process.c	(working copy)
@@ -660,6 +660,7 @@
 	case PT_TO_SCX:
 	case PT_SYSCALL:
 	case PT_FOLLOW_FORK:
+	case PT_FOLLOW_EXEC:
 	case PT_DETACH:
 		sx_xlock(&proctree_lock);
 		proctree_locked = 1;
@@ -874,6 +875,17 @@
 			p->p_flag &= ~P_FOLLOWFORK;
 		break;
 
+	case PT_FOLLOW_EXEC:
+		if (data) {
+			p->p_flag |= P_FOLLOWEXEC;
+			p->p_stops |= S_PT_EXEC;
+		}
+		else {
+			p->p_flag &= ~P_FOLLOWEXEC;
+			p->p_stops &= ~S_PT_EXEC;
+		}
+		break;
+
 	case PT_STEP:
 	case PT_CONTINUE:
 	case PT_TO_SCE:
@@ -936,7 +948,8 @@
 					p->p_sigparent = SIGCHLD;
 			}
 			p->p_oppid = 0;
-			p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK);
+			p->p_flag &= ~(P_TRACED | P_WAITED | P_FOLLOWFORK | 
+				       P_FOLLOWEXEC);
 
 			/* should we send SIGCHLD? */
 			/* childproc_continued(p); */
Index: sys/sys/proc.h
===================================================================
--- sys/sys/proc.h	(revision 230617)
+++ sys/sys/proc.h	(working copy)
@@ -617,6 +617,7 @@
 #define	P_INMEM		0x10000000 /* Loaded into memory. */
 #define	P_SWAPPINGOUT	0x20000000 /* Process is being swapped out. */
 #define	P_SWAPPINGIN	0x40000000 /* Process is being swapped in. */
+#define	P_FOLLOWEXEC	0x80000000 /* Notify debugger of exec events. */
 
 #define	P_STOPPED	(P_STOPPED_SIG|P_STOPPED_SINGLE|P_STOPPED_TRACE)
 #define	P_SHOULDSTOP(p)	((p)->p_flag & P_STOPPED)
Index: sys/sys/ptrace.h
===================================================================
--- sys/sys/ptrace.h	(revision 230617)
+++ sys/sys/ptrace.h	(working copy)
@@ -64,6 +64,7 @@
 #define	PT_SYSCALL	22
 
 #define	PT_FOLLOW_FORK	23
+#define	PT_FOLLOW_EXEC  24
 
 #define PT_GETREGS      33	/* get general-purpose registers */
 #define PT_SETREGS      34	/* set general-purpose registers */
@@ -142,6 +143,7 @@
  */
 #define	S_PT_SCE	0x000010000
 #define	S_PT_SCX	0x000020000
+#define	S_PT_EXEC	0x000080000
 
 int	ptrace_set_pc(struct thread *_td, unsigned long _addr);
 int	ptrace_single_step(struct thread *_td);