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

Simon Horman
2023-09-30T18:16:30Z

On Fri, Sep 29, 2023 at 03:51:48PM +0000, Haiyang Zhang wrote:
>
>
> > -----Original Message-----
> > From: Simon Horman <horms@kernel.org>
> > Sent: Friday, September 29, 2023 1:51 AM
> > To: Haiyang Zhang <haiyangz@microsoft.com>
> > Cc: linux-hyperv@vger.kernel.org; netdev@vger.kernel.org; Dexuan Cui
> > <decui@microsoft.com>; KY Srinivasan <kys@microsoft.com>; Paul Rosswurm
> > <paulros@microsoft.com>; olaf@aepfle.de; vkuznets
> > <vkuznets@redhat.com>; davem@davemloft.net; wei.liu@kernel.org;
> > edumazet@google.com; kuba@kernel.org; pabeni@redhat.com;
> > leon@kernel.org; Long Li <longli@microsoft.com>;
> > ssengar@linux.microsoft.com; linux-rdma@vger.kernel.org;
> > daniel@iogearbox.net; john.fastabend@gmail.com; bpf@vger.kernel.org;
> > ast@kernel.org; Ajay Sharma <sharmaajay@microsoft.com>;
> > hawk@kernel.org; tglx@linutronix.de; shradhagupta@linux.microsoft.com;
> > linux-kernel@vger.kernel.org; stable@vger.kernel.org
> > 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@vger.kernel.org
> > > > Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure
> > Network Adapter (MANA)")
> > > > Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> > >
> > > Reviewed-by: Simon Horman <horms@kernel.org>
> >
> > 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 for the clarification.