Re: [PATCH net-next v12 4/4] net: mana: recover port on attach failure in ethtool operations

[Paolo Abeni]

On 7/11/26 6:10 AM, Dipayaan Roy wrote:
> When mana_attach() fails during ethtool ring size or channel count
> changes, the port is left in a broken state with no recovery
> mechanism, requiring manual intervention to bring the port back up.
> 
> On VM SKUs without a netvsc fallback interface, this results in
> complete loss of network connectivity to the VM.
> 
> Fix by scheduling queue_reset_work when mana_attach() fails. The
> preceding patch ensures mana_detach() always completes its full
> teardown (netif_device_detach + cleanup), so the reset handler's
> mana_detach() takes the "already detached" early return, preserving
> port_st_save for a successful mana_attach() recovery.
> 
> When mana_attach() fails, choose retry values that maximize recovery
> chances: if the operation was an increase, fall back to the previous
> working values; if it was a decrease but still above default, fall
> back to defaults; otherwise use the minimum supported values.
> 
> Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Tested-by: Aditya Garg <gargaditya@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Dipayaan Roy <dipayanroy@xxxxxxxxxxxxxxxxxxx>
sashiko gemini sees quite a bit of problem with the above approach:

https://sashiko.dev/#/patchset/20260711041415.3008868-1-dipayanroy%40linux.microsoft.com

Also, changing user-setting in case of fallback is quite a bad thing to
be avoided.

Skimming over the code, it looks like than pre-allocate all the
resources and to a replace instead of detach/attach() looks feasible. I
suggest investigating such path. I also think that this last patch (and
possibly 2/4) could/should be in separate series.

Finally and most relevant thing; AI review comments should be explicitly
acknowledged by either debating them or addressing them. In both cases a
reply on the ML is expected.

/P