arm/183668: Panic when read unalign in ddb

[Howard Su]

>Number:         183668
>Category:       arm
>Synopsis:       Panic when read unalign in ddb
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-arm
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Nov 05 02:20:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Howard Su
>Release:        FreeBSD-Current
>Organization:
>Environment:
FreeBSD beaglebone 11.0-CURRENT FreeBSD 11.0-CURRENT #0 r257039: Thu Oct 24 11:39:07 CET 2013
>Description:
when read some memory in DDB unalign, the system will get reset. this is inconsistent with i386 behavior.
>How-To-Repeat:
Ctrl-Break, enter DDB
type 'dump thread 1'
>Fix:
Index: sys/arm/arm/trap.c
===================================================================
--- sys/arm/arm/trap.c	(revision 257663)
+++ sys/arm/arm/trap.c	(working copy)
@@ -528,7 +528,8 @@
 
 #ifdef KDB
 	if (debugger_on_panic || kdb_active)
-		kdb_trap(fsr, 0, tf);
+		if (kdb_trap(fsr, 0, tf))
+			return 0;
 #endif
 	panic("Fatal abort");
 	/*NOTREACHED*/


>Release-Note:
>Audit-Trail:
>Unformatted: