netdev - Re: suspicius csum initialization in vmxnet3_rx

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Date:   Tue, 5 Jun 2018 12:15:37 -0700
From:   Ronak Doshi <doshir@...are.com>
To:     Paolo Abeni <pabeni@...hat.com>
CC:     Neil Horman <nhorman@...driver.com>,
        Guolin Yang <gyang@...are.com>, Boon Ang <bang@...are.com>,
        Louis Luo <llouis@...are.com>, <netdev@...r.kernel.org>
Subject: Re: suspicius csum initialization in vmxnet3_rx_csum



On Tue, 5 Jun 2018, Paolo Abeni wrote:

> Hi,
> 
> I'm sorry for the long delay in my answer, I've been travelling.
> 
> On Fri, 2018-06-01 at 11:10 -0700, Ronak Doshi wrote:
> > On Thu, 31 May 2018, Neil Horman wrote:
> > > What packet types will rcd.csum be set for?
> > > Neil 
> > 
> > I looked thorugh the emulation code and found that rcd.csum is not set. 
> > For valid v4/v6, TCP/UDP packets the code block above the mentioend "if" 
> > block will be executed or else it will go through checksum none.
> > 
> > That's why I wanted to know (in previous emails) which ESX build is being 
> > used while this was tested. The code block under "if (gdesc->rcd.csum)" 
> > block might seem incorrect but it shouldn't be hit as rcd.csum is not set. 
> 
> I'm unsure if I read the above correctly. Do you mean that the relevant
> code-path is never hit? If so, can we simply drop it, as we agreed that
> such code is uncorrect? Elsewhere, could you plese specify under which
> circumstances gdesc->rcd.csum is filled by the hypervisor?
>
I do not see hypervisor populating rcd.csum field or may be the code has 
changed over the years. So, the codepath should not be hit as it is not 
populated. I will check and fix it or remove the block if not required. 
But as far as your issue is concerned, that code block is not hit.
 
Thanks,
Ronak