RE: [PATCH net, 1/3] net: mana: Fix TX CQE error handling

[Haiyang Zhang]

> -----Original Message-----
> From: Simon Horman <horms@xxxxxxxxxx>
> Sent: Friday, September 29, 2023 1:51 AM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
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> Subject: Re: [PATCH net, 1/3] net: mana: Fix TX CQE error handling
> 
> On Fri, Sep 29, 2023 at 07:47:57AM +0200, Simon Horman wrote:
> > On Sat, Sep 23, 2023 at 06:31:45PM -0700, Haiyang Zhang wrote:
> > > For an unknown TX CQE error type (probably from a newer hardware),
> > > still free the SKB, update the queue tail, etc., otherwise the
> > > accounting will be wrong.
> > >
> > > Also, TX errors can be triggered by injecting corrupted packets, so
> > > replace the WARN_ONCE to ratelimited error logging, because we don't
> > > need stack trace here.
> > >
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure
> Network Adapter (MANA)")
> > > Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> >
> > Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
> 
> Sorry, one latent question.
> 
> The patch replaces WARN_ONCE with a net_ratelimit()'d netdev_err().
> But I do wonder if, as a fix, netdev_err_once() would be more appropriate.

This error may happen with different CQE error types, so I use netdev_err() 
to display them, and added rate limit.

Thanks
- Haiyang