From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eduardo Pereira Habkost <ehabkost@conectiva.com.br>
Subject: Experimental fix for my memcpy_{to,from}fs problem
Date: Tue, 1 Jun 2004 19:02:35 -0300
Sender: linux-8086-owner@vger.kernel.org
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The following patch fixes the problem on my system. Probably
with some versions of bcc the patch will break something.

I've added code to save the contents of SI and DI, I don't know if the
callers of these functions assume that SI and DI are touched, but just
in case.

Now the system booted and ran flawlessly.

--- elks/arch/i86/mm/user.c	3 Jun 2002 22:22:58 -0000	1.15
+++ elks/arch/i86/mm/user.c	1 Jun 2004 20:44:51 -0000
@@ -34,10 +34,12 @@
=20
 #ifndef S_SPLINT_S
 #asm
+	push	si
+	push	di
 	mov	dx,es
 	mov	bx,ds
 	mov	es,bx
-	mov	ax,[bp-6]	! source segment (local variable)
+	mov	ax,[bp-2]	! source segment (local variable)
 	mov	ds,ax
 	mov	di,[bp+4]	! destination address
 	mov	si,[bp+6]	! source address
@@ -47,8 +49,11 @@
 	movsb
 	mov	ds,bx
 	mov	es,dx
+	pop	di
+	pop	si
 #endasm
 #endif
+
 }
=20
 int verified_memcpy_fromfs(void *daddr, void *saddr, size_t len)
@@ -69,8 +74,10 @@
=20
 #ifndef S_SPLINT_S
 #asm
+	push	si
+	push	di
 	mov	dx,es
-	mov	ax,[bp-6]	! source segment (local variable)
+	mov	ax,[bp-2]	! source segment (local variable)
 	mov	es,ax
 	mov	di,[bp+4]	! destination address
 	mov	si,[bp+6]	! source address
@@ -79,6 +86,8 @@
 	rep
 	movsb
 	mov	es,dx
+	pop	di
+	pop	si
 #endasm
 #endif
 }

--=20
Eduardo

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