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Date: Fri, 15 Dec 2023 10:59:28 +0100
From: Maxime Chevallier <maxime.chevallier@bootlin.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>, Paolo Abeni
 <pabeni@redhat.com>, Daniel Golle <daniel@makrotopia.org>, Heiner Kallweit
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 Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>,
 netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: phy: skip LED triggers on PHYs on SFP modules
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Hi Andrew,

On Fri, 15 Dec 2023 10:46:18 +0100
Andrew Lunn <andrew@lunn.ch> wrote:

> > I disagree with that - analysing the locking and coming up with a fix
> > is likely going to be a lengthy affair, meanwhile the mainline kernel
> > will deadlock on this. This patch prevents that deadlock at the
> > expense of removing the LED triggers for the PHY-on-SFP which I don't
> > think is a big deal considering the age of the PHY-based LED triggers.
> > 
> > So I personally would prefer this patch to be merged while a
> > different solution (that we have little idea at this point what it
> > would look like) is sought.  

I would agree, I feel bad about delaying it , although as Daniel
mentioned it's indeed the trigger registration that gets skipped.
 
> So, if i'm reading this patch correctly, it only affects PHYs within
> SFPs.
> 
> The discussion went off on a tangent and also talked about media
> converter PHYs, but from my reading of this patch, they are unaffected
> by this patch. Do they however also suffer from this deadlock? Anybody
> tested that?

I can give it a try today (in a few hours probably, I'm experiencing
a power outage right now...) and make sure the issue doesn't occur with
media converter PHYs.

Maxime

>      Andrew