linux-kernel - Re: [PATCH net] net: phylink: add missing supported link modes for the fixed-link

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: <aRbxmCPDe5ybYGwO@shell.armlinux.org.uk>
Date: Fri, 14 Nov 2025 09:08:40 +0000
From: "Russell King (Oracle)" <linux@...linux.org.uk>
To: Wei Fang <wei.fang@....com>
Cc: "andrew@...n.ch" <andrew@...n.ch>,
	"hkallweit1@...il.com" <hkallweit1@...il.com>,
	"davem@...emloft.net" <davem@...emloft.net>,
	"edumazet@...gle.com" <edumazet@...gle.com>,
	"kuba@...nel.org" <kuba@...nel.org>,
	"pabeni@...hat.com" <pabeni@...hat.com>,
	"eric@...int.com" <eric@...int.com>,
	"maxime.chevallier@...tlin.com" <maxime.chevallier@...tlin.com>,
	"imx@...ts.linux.dev" <imx@...ts.linux.dev>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH net] net: phylink: add missing supported link modes for
 the fixed-link

On Fri, Nov 14, 2025 at 08:52:07AM +0000, Wei Fang wrote:
> > On Fri, Nov 14, 2025 at 01:28:08PM +0800, Wei Fang wrote:
> > > Pause, Asym_Pause and Autoneg bits are not set when pl->supported is
> > > initialized, so these link modes will not work for the fixed-link.
> > 
> > What problem does this cause?
> > 
> 
> Our i.MX943 platform, the switch CPU port is connected to an ENETC
> MAC, the link speed is 2.5Gbps. And one user port of switch is 1Gbps.
> If the flow-control of internal link is not enabled, we can see the iperf
> performance of TCP packets is very low. Because of the congestion
> (ingress speed of CPU port is greater than egress speed of user port) in
> the switch, some TCP packets were dropped, resulting in the packets
> being retransmitted many times.

Please include this in the commit message, thanks.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!