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

Haiyang Zhang
2023-09-29T15:51:57Z

> -----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
- Haiyang