Re: [PATCH net V2 10/11] net/mlx5e: Update and set Xon/Xoff upon port speed set

[Tariq Toukan]

On 17/09/2025 16:00, Daniel Zahka wrote:
> On 9/17/25 6:39 AM, Tariq Toukan wrote:
> > On 15/09/2025 10:38, Tariq Toukan wrote:
> > > On 11/09/2025 17:36, Jakub Kicinski wrote:
> > > > On Thu, 11 Sep 2025 17:25:22 +0300 Mark Bloch wrote:
> > > > > On 11/09/2025 16:47, Jakub Kicinski wrote:
> > > > > > On Wed, 10 Sep 2025 17:00:11 -0700 Jakub Kicinski wrote:
> > > > > > > Hi, this is breaking dual host CX7 w/ 28.45.1300 (but I think most
> > > > > > > older FW versions, too). Looks like the host is not receiving any
> > > > > > > mcast (ping within a subnet doesn't work because the host receives
> > > > > > > no ndisc), and most traffic slows down to a trickle.
> > > > > > > Lost of rx_prio0_buf_discard increments.
> > > > > > >
> > > > > > > Please TAL ASAP, this change went to LTS last week.
> > > > > >
> > > > > > Any news on this? I heard that it also breaks DCB/QoS configuration
> > > > > > on 6.12.45 LTS.
> > > > >
> > > > > We are looking into this, once we have anything I'll update.
> > > > > Just to make sure, reverting this is one commit solves the
> > > > > issue you are seeing?
> > > >
> > > > It did for me, but Daniel (who is working on the PSP series)
> > > > mentioned that he had reverted all three to get net-next working:
> > > >
> > > >    net/mlx5e: Set local Xoff after FW update
> > > >    net/mlx5e: Update and set Xon/Xoff upon port speed set
> > > >    net/mlx5e: Update and set Xon/Xoff upon MTU set
> > >
> > > Hi Jakub,
> > >
> > > Thanks for reporting.
> > > We're investigating and will update soon.
> > >
> > > Regards,
> > > Tariq
> >
> > Hi,
> >
> > We prefer reverting the single patch [1] for now. We'll submit a fixed 
> > version later.
> >
> > Regarding the other two patches [2], initial testing showed no issues.
> > Can you/Daniel share more info? What issues you see, and the repro steps.
> >
> > Thanks,
> > Tariq
> >
> > [1]
> > net/mlx5e: Update and set Xon/Xoff upon port speed set
> >
> > [2]
> > net/mlx5e: Set local Xoff after FW update
> > net/mlx5e: Update and set Xon/Xoff upon MTU set
>
> Hello Tariq,
>
> My notes for the situation were that I was running a vanilla net-next 
> kernel on a dual host, CX7 system, with the 28.45.1300 FW at commit:
>
> deb105f49879 net: phy: marvell: Fix 88e1510 downshift counter errata
>
> and I was having the issues that Jakub described. No ping working in a 
> subnet. Extremely slow bandwidth on a large transfer. My notes say that 
> reverting just [1] (from your message) did not fix the problem, but then 
> reverting [2] and [3] restored normal behavior.
>
> However, I did attempt to reproduce again on the same system this 
> morning, and now I'm seeing that reverting just [1] is sufficient to fix 
> the issues.

I see.
For now, I'll submit a revert only for [1].

Let us know of any related issue you still hit after the revert.

Thanks.