Index: head/sys/powerpc/powerpc/sigcode64.S
===================================================================
--- head/sys/powerpc/powerpc/sigcode64.S	(revision 356855)
+++ head/sys/powerpc/powerpc/sigcode64.S	(revision 356856)
@@ -1,76 +1,80 @@
 /* $FreeBSD$ */
 /* $NetBSD: sigcode.S,v 1.1 1999/11/17 14:56:11 kleink Exp $	*/
 
 /*-
  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
  * Copyright (C) 1995, 1996 TooLs GmbH.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
  *    must display the following acknowledgement:
  *	This product includes software developed by TooLs GmbH.
  * 4. The name of TooLs GmbH may not be used to endorse or promote products
  *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include <machine/asm.h>
 #include <sys/syscall.h>
 #include "assym.inc"
 
 /*
  * The following code gets copied to the top of the user stack on process
  * execution.  It does signal trampolining on signal delivery.
  *
  * On entry r1 points to a struct sigframe at bottom of current stack.
  * All other registers are unchanged.
  *
  * Entered midway through for v2 ELF binaries that don't need to deal with
  * function descriptors.
  *
  */
 	.globl	CNAME(sigcode64),CNAME(szsigcode64)
 	.globl	CNAME(sigcode64_elfv2),CNAME(szsigcode64_elfv2)
 CNAME(sigcode64):
 	mflr	2			/* resolve function descriptor */
 	ld	0,0(2)			
 	ld	2,8(2)
 	mtlr	0
 
 CNAME(sigcode64_elfv2):
 	addi	1,1,-112		/* reserved space for callee */
 	mflr	12			/* ELFv2 wants the address in r12 */
 	blrl
 
 	addi	3,1,112+SF_UC		/* restore sp, and get &frame->sf_uc */
 	li	0,SYS_sigreturn
 	sc				/* sigreturn(scp) */
+	/*
+	 * If we get back to here, it means sigreturn failed.
+	 * As such, we are now stuck in the wrong context.
+	 * Exit immediately without touching the stack.
+	 */
 	li	0,SYS_exit
 	sc				/* exit(errno) */
-	nop				/* align to doubleword */
 endsigcode64:
 	
 	.data
 CNAME(szsigcode64):
 	.long	endsigcode64 - CNAME(sigcode64)
 CNAME(szsigcode64_elfv2):
 	.long	endsigcode64 - CNAME(sigcode64_elfv2)