Index: sys/ddb/db_ps.c
===================================================================
--- sys/ddb/db_ps.c
+++ sys/ddb/db_ps.c
@@ -107,7 +107,7 @@
 db_ps(db_expr_t addr, bool hasaddr, db_expr_t count, char *modif)
 {
 	struct proc *p;
-	int i, j;
+	int i;
 
 	ps_mode = modif[0] == 'a' ? PRINT_ARGS : PRINT_NONE;
 
@@ -125,14 +125,12 @@
 		db_ps_proc(p);
 
 	/*
-	 * Do zombies.
+	 * Processes such as zombies not in allproc.
 	 */
-	for (i = 0; i < pidhashlock + 1 && !db_pager_quit; i++) {
-		for (j = i; j <= pidhash && !db_pager_quit; j += pidhashlock + 1) {
-			LIST_FOREACH(p, &pidhashtbl[j], p_hash) {
-				if (p->p_state == PRS_ZOMBIE)
-					db_ps_proc(p);
-			}
+	for (i = 0; i <= pidhash && !db_pager_quit; i++) {
+		LIST_FOREACH(p, &pidhashtbl[i], p_hash) {
+			if ((p->p_flag2 & P2_ALLPROC_REMOVED) != 0)
+				db_ps_proc(p);
 		}
 	}
 }
Index: sys/kern/kern_exit.c
===================================================================
--- sys/kern/kern_exit.c
+++ sys/kern/kern_exit.c
@@ -440,6 +440,7 @@
 
 	sx_xlock(&proctree_lock);
 	PROC_LOCK(p);
+	p->p_flag2 |= P2_ALLPROC_REMOVED;
 	p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE);
 	PROC_UNLOCK(p);
 
Index: sys/sys/proc.h
===================================================================
--- sys/sys/proc.h
+++ sys/sys/proc.h
@@ -811,6 +811,7 @@
 						   MAP_STACK */
 #define	P2_STKGAP_DISABLE_EXEC	0x00001000	/* Stack gap disabled
 						   after exec */
+#define	P2_ALLPROC_REMOVED	0x00002000	/* Removed from allproc list. */
 
 /* Flags protected by proctree_lock, kept in p_treeflags. */
 #define	P_TREE_ORPHANED		0x00000001	/* Reparented, on orphan list */