Re: [dpdk-dev] [PATCH v4] ixgbe: Drop flow control frames from VFs

["Zhang, Helin" <helin.zhang@intel.com>]

> -----Original Message-----
> From: Vlad Zolotarov [mailto:vladz@cloudius-systems.com]
> Sent: Friday, October 23, 2015 4:27 PM
> To: Zhang, Helin
> Cc: Lu, Wenzhuo; dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v4] ixgbe: Drop flow control frames from VFs
> 
> 
> 
> On 10/23/15 10:14, Zhang, Helin wrote:
> >
> > From: Vladislav Zolotarov [mailto:vladz@cloudius-systems.com]
> > Sent: Friday, October 23, 2015 2:57 PM
> > To: Zhang, Helin
> > Cc: Lu, Wenzhuo; dev@dpdk.org
> > Subject: RE: [dpdk-dev] [PATCH v4] ixgbe: Drop flow control frames
> > from VFs
> >
> >
> > On Oct 23, 2015 9:30 AM, "Zhang, Helin" <helin.zhang@intel.com> wrote:
> >>
> >>
> >> From: Vladislav Zolotarov [mailto:vladz@cloudius-systems.com]
> >> Sent: Friday, October 23, 2015 2:24 PM
> >> To: Zhang, Helin
> >> Cc: Lu, Wenzhuo; dev@dpdk.org
> >> Subject: Re: [dpdk-dev] [PATCH v4] ixgbe: Drop flow control frames
> >> from VFs
> >>
> >>
> >> On Oct 23, 2015 9:02 AM, "Zhang, Helin" <helin.zhang@intel.com> wrote:
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Lu, Wenzhuo
> >>>> Sent: Friday, October 23, 2015 1:52 PM
> >>>> To: dev@dpdk.org
> >>>> Cc: Zhang, Helin; Lu, Wenzhuo
> >>>> Subject: [PATCH v4] ixgbe: Drop flow control frames from VFs
> >>>>
> >>>> This patch will drop flow control frames from being transmitted from VSIs.
> >>>> With this patch in place a malicious VF cannot send flow control or
> >>>> PFC packets out on the wire.
> >> The whole idea of this (and similar i40e patches sent before) is really
> confusing.
> >> If u want to disable FC feature for VFs then go and disable the feature. Why
> keep (not malicious) user think that he/she has enabled the feature while u
> silently block it?
> >>
> >> Helin: I don't think disabling FC is equal to filtering out any pause frames. How
> about the software application constructs a pause frame and then tries to send it
> out?
> > But not disabling FC for the user and silently preventing it is bogus. First, the
> conventional user should not be affected. I think this patch (and all its clones)
> should be extended to, first, disable the FC Tx feature for the relevant devices
> and only then adding any anti malicious filtering.
> >
> > Helin: Disabling FC will disable both PF and VF FC, I don't find out where can
> disable VF FC only. Am I wrong?
> 
> There are flow_ctrl_get/set callbacks in eth_dev_ops which are used for
> configuring FC.
> I see that they are not set for either ixgbevf or i40evf, so here we are all set for
> these.
Helin: The behaviors rely on the hardware capability, but not the SW.
I meant I don't think it can support disabling VF FC. Please correct me in case I am wrong!


> 
> >
> >>>> V2:
> >>>> Reword the comments.
> >>>>
> >>>> V3:
> >>>> Move the check of set_ethertype_anti_spoofing to the top of the function,
> to
> >>>> avoid occupying an ethertype_filter entity without using it.
> >>>>
> >>>> V4:
> >>>> Remove the useless braces and return.
> >>>>
> >>>> Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
> >>> Acked-by: Helin Zhang <helin.zhang@intel.com>
> >>>