Re: [Intel-wired-lan] [PATCH] e1000e: Make speed detection on hotplugging cable more reliable

[Kai Heng Feng]

at 5:06 PM, Paul Menzel <pmenzel@xxxxxxxxxxxxx> wrote:

> Dear Kai Heng,
>
>
> (with or without hyphen?)
>
> On 7/15/19 11:00 AM, Kai Heng Feng wrote:
> > at 4:52 PM, Paul Menzel <pmenzel@xxxxxxxxxxxxx> wrote:
>
> > > On 7/15/19 10:43 AM, Kai-Heng Feng wrote:
> > > > After hotplugging an 1Gbps ethernet cable with 1Gbps link partner, the
> > > > MII_BMSR may reports 10Mbps, renders the network rather slow.
> > >
> > > s/may reports/may report/
> > > s/renders/rendering/
> >
> > Apparently English isnât my mother tongue ;)
>
> No problem. Mine neither.
>
> > > > The issue has much lower fail rate after commit 59653e6497d1 ("e1000e:
> > > > Make watchdog use delayed work"), which esssentially introduces some
> > >
> > > essentially
> >
> > Ok.
> >
> > > > delay before running the watchdog task.
> > > >
> > > > But there's still a chance that the hotplugging event and the queued
> > > > watchdog task gets run at the same time, then the original issue can be
> > > > observed once again.
> > > >
> > > > So let's use mod_delayed_work() to add a deterministic 1 second delay
> > > > before running watchdog task, after an interrupt.
> > >
> > > I am not clear about the effects for the user. Could you elaborate
> > > please? Does the link now come up up to one second later?
> >
> > Yes, the link will be up on a fixed one second later.
> >
> > The delay varies between 0 to 2 seconds without this patch.
>
> Is there no other fix? Regarding booting a system fast (less than six
> seconds), a fixed one second delay is quite a regression on systems where
> it worked before.

This only affects when ethernet cable is hot plugged.

Kai-Heng

> > > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> > >
> > > Any bug URL?
> >
> > If maintainers think itâs necessary then Iâll file one.
>
> Not necessary, if there is none. I thought you had one in Launchpad or so.
>
>
> Kind regards,
>
> Paul