RE: [PATCH v6 2/2] net/ixgbe: Fix SFP detection and linking on hotplug

["Wang, Haiyue" <haiyue.wang@intel.com>]

> -----Original Message-----
> From: Morten Brørup <mb@smartsharesystems.com>
> Sent: Wednesday, April 13, 2022 14:58
> To: Wang, Haiyue <haiyue.wang@intel.com>; Daly, Jeff <jeffd@silicom-usa.com>; dev@dpdk.org
> Cc: stable@dpdk.org; Stephen Douthit <stephend@silicom-usa.com>; Yang, Qiming <qiming.yang@intel.com>
> Subject: RE: [PATCH v6 2/2] net/ixgbe: Fix SFP detection and linking on hotplug
> 
> > From: Wang, Haiyue [mailto:haiyue.wang@intel.com]
> > Sent: Wednesday, 13 April 2022 04.47
> > To: Daly, Jeff; dev@dpdk.org
> > Cc: stable@dpdk.org; Stephen Douthit; Yang, Qiming
> >
> > > From: Jeff Daly <jeffd@silicom-usa.com>
> > > Sent: Wednesday, April 13, 2022 01:42
> > > To: dev@dpdk.org
> > > Cc: stable@dpdk.org; Stephen Douthit <stephend@silicom-usa.com>;
> > Wang, Haiyue <haiyue.wang@intel.com>
> > >
> > > Currently the ixgbe driver does not ID any SFP except for the first
> > one
> > > plugged in. This can lead to no-link, or incorrect speed conditions.
> > >
> > > For example:
> > >
> > > * If link is initially established with a 1G SFP, and later a 1G/10G
> > > multispeed part is later installed, then the MAC link setup functions
> > are
> > > never called to change from 1000BASE-X to 10GBASE-R mode, and the
> > link
> > > stays running at the slower rate.
> > >
> > > * If link is initially established with a 1G SFP, and later a 10G
> > only
> > > module is later installed, no link is established, since we are still
> > > trasnsmitting in 1000BASE-X mode to a 10GBASE-R only partner.
> > >
> > > Refactor the SFP ID/setup, and link setup code, to more closely match
> > the
> > > flow of the mainline kernel driver which does not have these issues.
> > In
> > > that driver a service task runs periodically to handle these
> > operations
> > > based on bit flags that have been set (usually via interrupt or
> > userspace
> > > request), and then get cleared once the requested subtask has been
> > > completed.
> > >
> > > Fixes: af75078fece ("first public release")
> > > Cc: stable@dpdk.org
> > >
> >
> > So BIG change for new platform, DON'T CC to stable!
> 
> What do you mean by "new platform"? The ixgbe hardware and driver is not new.
> 

It's soc NIC, ixgbe not support before.

> This patch fixes a bug (with a serious impact when occurring), so it should be backported. The size of
> the patch does not disqualify it for backporting.
> 
> -Morten