[PATCH v1] net/vhost: clear data of packet mbuf after sending pkts

[Zhang, Yuying]

Hi Marchand,

> -----Original Message-----
> From: David Marchand <david.marchand at redhat.com>
> Sent: Tuesday, March 1, 2022 4:44 PM
> To: Zhang, Yuying <yuying.zhang at intel.com>
> Cc: dev <dev at dpdk.org>; Maxime Coquelin <maxime.coquelin at redhat.com>;
> Xia, Chenbo <chenbo.xia at intel.com>; dpdk stable <stable at dpdk.org>
> Subject: Re: [PATCH v1] net/vhost: clear data of packet mbuf after sending pkts
> 
> On Tue, Mar 1, 2022 at 8:29 AM Yuying Zhang <yuying.zhang at intel.com> wrote:
> >
> > The PMD frees a packet mbuf back into its original mempool after
> > sending a packet. However, old data is not cleaned up which causes
> > error in payload of new packets. This patch clear data of packet mbuf
> > before freeing mbuf.
> 
> This patch looks wrong to me.
> What is the actual issue you want to fix?

eth_vhost_tx() frees the packet mbuf back into its original mempool every time after a packet sent without clearing the data field.
Then packet transmit  function will get bulk directly without reset. New generated packet contains old data of previous packet. This is wrong.

> 
> 
> --
> David Marchand