Re: [Qemu-devel] [PATCH v2] e1000: Fix multi-descriptor packet checksum offload

[Aurelien Jarno]

On Mon, Mar 07, 2011 at 08:04:07PM +0000, Stefan Hajnoczi wrote:
> The PCI/PCI-X Family of Gigabit Ethernet Controllers Software
> Developer’s Manual states the following about the POPTS field:
> 
>   Provides a number of options which control the handling of this
>   packet.  This field is ignored except on the first data descriptor of
>   a packet.
> 
> The current implementation always loads the field and its checksum
> offload flags.  This patch uses only the first descriptor's POPTS field
> in order to comply with the specification.
> 
> When Solaris sends multi-descriptor packets it fills in POPTS for the
> first descriptor only.  Therefore this patch is necessary in order to
> perform checksum offload correctly for multi-descriptor packets.
> 
> Reported-by: Daniel Pecka <address@hidden>
> Reported-by: Gabriele A. Trombetti <address@hidden>
> Signed-off-by: Stefan Hajnoczi <address@hidden>
> ---
> v2:
>  * Fix Reported-by: details
> 
>  hw/e1000.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)

Thanks, applied.

> diff --git a/hw/e1000.c b/hw/e1000.c
> index 0a4574c..2a4d5c7 100644
> --- a/hw/e1000.c
> +++ b/hw/e1000.c
> @@ -446,7 +446,9 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)
>          return;
>      } else if (dtype == (E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D)) {
>          // data descriptor
> -        tp->sum_needed = le32_to_cpu(dp->upper.data) >> 8;
> +        if (tp->size == 0) {
> +            tp->sum_needed = le32_to_cpu(dp->upper.data) >> 8;
> +        }
>          tp->cptse = ( txd_lower & E1000_TXD_CMD_TSE ) ? 1 : 0;
>      } else {
>          // legacy descriptor
> -- 
> 1.7.2.3
> 
> 
> 

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
address@hidden                 http://www.aurel32.net