netdev - Re: [PATCH RFC net-next] net: phylink: always config mac for (delayed) phy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ed29e632-332b-4af1-bf7f-97498297e731@lunn.ch>
Date: Tue, 7 Jan 2025 14:20:31 +0100
From: Andrew Lunn <andrew@...n.ch>
To: Eric Woudstra <ericwouds@...il.com>
Cc: "Russell King (Oracle)" <linux@...linux.org.uk>,
	Heiner Kallweit <hkallweit1@...il.com>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	Matthias Brugger <matthias.bgg@...il.com>,
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
	Frank Wunderlich <frank-w@...lic-files.de>,
	Daniel Golle <daniel@...rotopia.org>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org, netfilter-devel@...r.kernel.org,
	coreteam@...filter.org, bridge@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org
Subject: Re: [PATCH RFC net-next] net: phylink: always config mac for
 (delayed) phy

> I think it is because pl->act_link_an_mode stays at MLO_AN_INBAND, but
> it needs to be set to MLO_AN_PHY, so that only the phy determines the
> link state:
> 
> phylink_resolve() {
>     ...
> 	} else if (pl->act_link_an_mode == MLO_AN_PHY) {
> 		link_state = pl->phy_state;
>     ...
> }

phylink tries to determine the whole chain is up. As Russell says, it
could be the PCS has not got sync with the PHY for some reason. So
even if you ignore the PCS state, it might not work. This is actually
a useful pieces of information. Does the link actually work end to end
if you only look at the media state? If it does, that would indicate
the PCS is maybe missing an interrupt, or needs polling for change in
state.

	Andrew