From: Tomas Hruby <tom@minix3.org>
Date: Fri, 26 Mar 2010 12:29:52 +0000 (+0000)
Subject: Direction flag
X-Git-Tag: v3.1.7~203
X-Git-Url: http://zhaoyanbai.com/repos/?a=commitdiff_plain;h=1dd6f5573ac4c32b827b6094063c83801e70491e;p=minix.git

Direction flag

- ack assumes that the direction flag in eflags is clear when
  assigning two structures. It is implemented by a call to a built-in
  function which is like memcpy but needs the flag to be clear
  otherwise rubish is copied. This patch fixes the kernel entries.
---

diff --git a/kernel/arch/i386/mpx386.S b/kernel/arch/i386/mpx386.S
index a768db586..fd46183ca 100644
--- a/kernel/arch/i386/mpx386.S
+++ b/kernel/arch/i386/mpx386.S
@@ -472,9 +472,6 @@ exception_entry:
 	TEST_INT_IN_KERNEL(12, exception_entry_nested)
 
 exception_entry_from_user:
-
-	cld
-
 	SAVE_PROCESS_CTX(8)
 
 	/* stop user process cycles */
diff --git a/kernel/arch/i386/sconst.h b/kernel/arch/i386/sconst.h
index 0bad53dd6..c5d32752b 100644
--- a/kernel/arch/i386/sconst.h
+++ b/kernel/arch/i386/sconst.h
@@ -121,6 +121,9 @@
  * value on the stack - error code and the exception number
  */
 #define SAVE_PROCESS_CTX_NON_LAZY(displ) \
+								\
+	cld /* set the direction flag to a known state */	;\
+								\
 	push	%ebp					;\
 							;\
 	movl	(CURR_PROC_PTR + 4 + displ)(%esp), %ebp	;\