Re: [Qemu-devel] [PATCH 2/2] s390x/css: fix bits must be zero check for TIC

[Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>]

Hello Halil,

* Halil Pasic <pasic@linux.vnet.ibm.com> [2017-07-26 00:44:42 +0200]:

> According to the PoP bit positions 0-3 and 8-32 of the format-1 CCW must
> contain zeros.  Bits 0-3 are already covered by cmd_code validity
> checking, and bit 32 is covered by the CCW address checking.
> 
> Bits 8-31 correspond to CCW1.flags and CCW1.count.  Currently we only
> check for the absence of certain flags.  Let's fix this.
> 
> Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
> ---
>  hw/s390x/css.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
> index d17e21b7af..1f04ce4a1b 100644
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -884,7 +884,8 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
>              ret = -EINVAL;
>              break;
>          }
> -        if (ccw.flags & (CCW_FLAG_CC | CCW_FLAG_DC)) {
> +        if (ccw.flags || ccw.count) {
> +            /* We have already sanitized these if fmt 0. */
ccw0 does not have the same restrictions as ccw1. We don't sanitize
these for ccw0.

(This comment is still here. Did I misunderstand things? :)

>              ret = -EINVAL;
>              break;
>          }
> -- 
> 2.11.2
> 

With the comment removed:
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>

-- 
Dong Jia Shi