netdev - Re: riscv defconfig CONFIG_PM/macb/generic PHY regression in v5.18-rc1

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: <YkxW68j5N4hVgY18@lunn.ch>
Date:   Tue, 5 Apr 2022 16:49:15 +0200
From:   Andrew Lunn <andrew@...n.ch>
To:     Conor.Dooley@...rochip.com
Cc:     palmer@...osinc.com, apatel@...tanamicro.com,
        netdev@...r.kernel.org, Nicolas.Ferre@...rochip.com,
        Claudiu.Beznea@...rochip.com, linux@...linux.org.uk,
        hkallweit1@...il.com, linux-riscv@...ts.infradead.org
Subject: Re: riscv defconfig CONFIG_PM/macb/generic PHY regression in
 v5.18-rc1

On Tue, Apr 05, 2022 at 02:18:17PM +0000, Conor.Dooley@...rochip.com wrote:
> 
> 
> On 05/04/2022 13:25, Andrew Lunn wrote:
> > On Tue, Apr 05, 2022 at 01:05:12PM +0000, Conor.Dooley@...rochip.com wrote:
> >> [ 2.818894] macb 20112000.ethernet eth0: PHY [20112000.ethernet-ffffffff:09] driver [Generic PHY] (irq=POLL)
> > 
> > Hi Conor
> > 
> > In general, it is better to use the specific PHY driver for the PHY
> > then rely on the generic PHY driver. I think the Icicle Kit has a
> > VSC8662? So i would suggest you enable the Vitesse PHYs.
> 
> Hi Andrew, thanks for the quick reply.
> It does indeed have a Vitesse VSC8662, but the link never seems to
> come up for me [1] so I have been using Generic PHY. I'll try look
> at why that is. Either way would like to know what's gone wrong in
> the Generic PHY case since that's what's available in the riscv
> defconfig.

Hi Conor

Generic PHY is purely best effort fall back for when there is nothing
better. It might work, it might not, depending on the PHY. If it is a
simple PHY which only implements the registers defined in 802.3 clause
22, and not much more, it has a good chance of working. Otherwise, you
really should be using the specific driver.

Don't worry too much about the defconfig, nobody actually uses
it. Distros have their own which turn on most things. So a real system
probably does have the correct PHY driver.

	 Andrew