--- a/usr/src/uts/common/os/fork.c	Thu Oct 27 09:08:47 2005 -0700
+++ b/usr/src/uts/common/os/fork.c	Thu Oct 27 13:18:49 2005 -0700
@@ -334,6 +334,7 @@
 		/* for each entry in the parent's lwp directory... */
 		for (i = 0, ldp = p->p_lwpdir; i < p->p_lwpdir_sz; i++, ldp++) {
 			klwp_t *clwp;
+			kthread_t *ct;
 
 			if ((lep = ldp->ld_entry) == NULL)
 				continue;
@@ -342,17 +343,22 @@
 				clwp = forklwp(ttolwp(t), cp, t->t_tid);
 				if (clwp == NULL)
 					goto forklwperr;
+				ct = lwptot(clwp);
 				/*
 				 * Inherit lwp_wait()able and daemon flags.
 				 */
-				lwptot(clwp)->t_proc_flag |=
+				ct->t_proc_flag |=
 				    (t->t_proc_flag & (TP_TWAIT|TP_DAEMON));
 				/*
 				 * Keep track of the clone of curthread to
 				 * post return values through lwp_setrval().
+				 * Mark other threads for special treatment
+				 * by lwp_rtt() / post_syscall().
 				 */
 				if (t == curthread)
 					clone = clwp;
+				else
+					ct->t_flag |= T_FORKALL;
 			} else {
 				/*
 				 * Replicate zombie lwps in the child.

--- a/usr/src/uts/common/sys/thread.h	Thu Oct 27 09:08:47 2005 -0700
+++ b/usr/src/uts/common/sys/thread.h	Thu Oct 27 13:18:49 2005 -0700
@@ -350,6 +350,7 @@
 #define	T_WAKEABLE	0x0002	/* thread is blocked, signals enabled */
 #define	T_TOMASK	0x0004	/* use lwp_sigoldmask on return from signal */
 #define	T_TALLOCSTK	0x0008  /* thread structure allocated from stk */
+#define	T_FORKALL	0x0010	/* thread was cloned by forkall() */
 #define	T_WOULDBLOCK	0x0020	/* for lockfs */
 #define	T_DONTBLOCK	0x0040	/* for lockfs */
 #define	T_DONTPEND	0x0080	/* for lockfs */

--- a/usr/src/uts/intel/ia32/os/syscall.c	Thu Oct 27 09:08:47 2005 -0700
+++ b/usr/src/uts/intel/ia32/os/syscall.c	Thu Oct 27 13:18:49 2005 -0700
@@ -19,8 +19,9 @@
  *
  * CDDL HEADER END
  */
+
 /*
- * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -589,6 +590,7 @@
 	 */
 	lwp->lwp_eosys = NORMALRETURN;
 	clear_stale_fd();
+	t->t_flag &= ~T_FORKALL;
 
 	/*
 	 * If a single-step trap occurred on a syscall (see trap())

--- a/usr/src/uts/sparc/os/syscall.c	Thu Oct 27 09:08:47 2005 -0700
+++ b/usr/src/uts/sparc/os/syscall.c	Thu Oct 27 13:18:49 2005 -0700
@@ -677,11 +677,14 @@
 		 * The default action is to redo the trap instruction.
 		 * We increment the pc and npc past it for NORMALRETURN.
 		 * JUSTRETURN has set up a new pc and npc already.
-		 * RESTARTSYS automatically restarts by leaving pc and npc
-		 * alone.
+		 * If we are a cloned thread of forkall(), don't
+		 * adjust here because we have already inherited
+		 * the adjusted values from our clone.
 		 */
-		rp->r_pc = rp->r_npc;
-		rp->r_npc += 4;
+		if (!(t->t_flag & T_FORKALL)) {
+			rp->r_pc = rp->r_npc;
+			rp->r_npc += 4;
+		}
 	}
 
 	/*
@@ -726,6 +729,7 @@
 	 */
 	lwp->lwp_eosys = NORMALRETURN;
 	clear_stale_fd();
+	t->t_flag &= ~T_FORKALL;
 
 	if (t->t_astflag | t->t_sig_check) {
 		/*

--- a/usr/src/uts/sparc/v9/ml/syscall_trap.s	Thu Oct 27 09:08:47 2005 -0700
+++ b/usr/src/uts/sparc/v9/ml/syscall_trap.s	Thu Oct 27 13:18:49 2005 -0700
@@ -578,7 +578,7 @@
 	ldn	[THREAD_REG + T_STACK], %l7
 	call	__dtrace_probe___proc_start
 	sub	%l7, STACK_BIAS, %sp
-	ba	0f
+	ba,a,pt	%xcc, 0f
 
 	ENTRY_NP(lwp_rtt)
 	ldn	[THREAD_REG + T_STACK], %l7
@@ -593,5 +593,6 @@
 	ldx	[%l7 + O1_OFF], %o1
 	ba,a,pt	%xcc, user_rtt
 	SET_SIZE(lwp_rtt)
+	SET_SIZE(lwp_rtt_initial)
 
 #endif	/* lint */