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Date: Fri, 15 Dec 2023 10:46:18 +0100
From: Andrew Lunn <andrew@lunn.ch>
To: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Paolo Abeni <pabeni@redhat.com>, Daniel Golle <daniel@makrotopia.org>,
	Maxime Chevallier <maxime.chevallier@bootlin.com>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric 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
Message-ID: <37a66b85-3980-4553-8447-d040404bbc11@lunn.ch>
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> 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.

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?

     Andrew