Re: Experimental fix for my memcpy_{to,from}fs problem

[Miguel Bolanos <mike@linuxlabs.com>]

Applied. Thanks.

Mike

On Tue, 2004-06-01 at 16:02, Eduardo Pereira Habkost wrote:
> 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 @@
>  
>  #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
> +
>  }
>  
>  int verified_memcpy_fromfs(void *daddr, void *saddr, size_t len)
> @@ -69,8 +74,10 @@
>  
>  #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
>  }