svn commit: r246036 - projects/amd64_xen_pv/sys/amd64/xen

[Cherry G. Mathew]

Author: cherry
Date: Mon Jan 28 17:25:53 2013
New Revision: 246036
URL: http://svnweb.freebsd.org/changeset/base/246036

Log:
  Exception handling stack bugs:
   i) Stop overwriting the previous stackframe
   ii) Restore stack frame *after* restoring registers after alignment check
  
  Approved by: gibbs (implicit)

Modified:
  projects/amd64_xen_pv/sys/amd64/xen/exception.S

Modified: projects/amd64_xen_pv/sys/amd64/xen/exception.S
==============================================================================
--- projects/amd64_xen_pv/sys/amd64/xen/exception.S	Mon Jan 28 15:48:31 2013	(r246035)
+++ projects/amd64_xen_pv/sys/amd64/xen/exception.S	Mon Jan 28 17:25:53 2013	(r246036)
@@ -131,10 +131,10 @@
 	subq 	$TF_ERR, %rsp
 
 #define TRAP_FRAME_EXIT_NOERR \
-	addq	$TF_RIP + 8, %rsp
+	addq	$TF_RIP, %rsp
 
 #define TRAP_FRAME_EXIT_ERR \
-	addq 	$TF_ERR + 8, %rsp
+	addq 	$TF_ERR, %rsp
 
 #define TRAP_PROLOGUE(a) \
 	movl	$(a), TF_TRAPNO(%rsp) 	; \
@@ -434,9 +434,9 @@ IDTVEC(ac)			/* Alignment-Check */
 	DO_STI_MAYBE		;
 	CALLTRAP		;
 	DO_AST_MAYBE		;
-	TRAP_FRAME_EXIT_ERR   	;
 	RESTORE_GENERAL_REGS	;
 	RESTORE_SEGMENT_REGS	;
+	TRAP_FRAME_EXIT_ERR   	;
 	INTR_EXIT		;
 
 IDTVEC(mc)			/* Machine-Check */