svn commit: r203572 - head/sys/ia64/ia64

[Marcel Moolenaar]

Author: marcel
Date: Sat Feb  6 20:46:14 2010
New Revision: 203572
URL: http://svn.freebsd.org/changeset/base/203572

Log:
  Fix single-stepping when the kernel was entered through the EPC syscall
  path. When the taken branch leaves the kernel and enters the process,
  we still need to execute the instruction at that address. Don't raise
  SIGTRAP when we branch into the process, but enable single-stepping
  instead.

Modified:
  head/sys/ia64/ia64/trap.c

Modified: head/sys/ia64/ia64/trap.c
==============================================================================
--- head/sys/ia64/ia64/trap.c	Sat Feb  6 20:41:25 2010	(r203571)
+++ head/sys/ia64/ia64/trap.c	Sat Feb  6 20:46:14 2010	(r203572)
@@ -803,7 +803,7 @@ trap(int vector, struct trapframe *tf)
 		 * out of the gateway page we'll get back into the kernel
 		 * and then we enable single stepping.
 		 * Since this a rather round-about way of enabling single
-		 * stepping, don't make things complicated even more by
+		 * stepping, don't make things even more complicated by
 		 * calling userret() and do_ast(). We do that later...
 		 */
 		tf->tf_special.psr &= ~IA64_PSR_LP;
@@ -814,13 +814,14 @@ trap(int vector, struct trapframe *tf)
 		/*
 		 * Don't assume there aren't any branches other than the
 		 * branch that takes us out of the gateway page. Check the
-		 * iip and raise SIGTRAP only when it's an user address.
+		 * iip and enable single stepping only when it's an user
+		 * address.
 		 */
 		if (tf->tf_special.iip >= VM_MAX_ADDRESS)
 			return;
 		tf->tf_special.psr &= ~IA64_PSR_TB;
-		sig = SIGTRAP;
-		break;
+		tf->tf_special.psr |= IA64_PSR_SS;
+		return;
 
 	case IA64_VEC_IA32_EXCEPTION:
 	case IA64_VEC_IA32_INTERCEPT: