netdev - Re: [PATCH net-next v2 0/2] net: phy: improve PHY suspend/resume

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: <20180601001043.GA2303@lunn.ch>
Date:   Fri, 1 Jun 2018 02:10:43 +0200
From:   Andrew Lunn <andrew@...n.ch>
To:     Heiner Kallweit <hkallweit1@...il.com>
Cc:     Florian Fainelli <f.fainelli@...il.com>,
        David Miller <davem@...emloft.net>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next v2 0/2] net: phy: improve PHY suspend/resume

> Configuring the different WoL options isn't handled by writing to
> the PHY registers but by writing to chip / MAC registers.
> Therefore phy_suspend() isn't able to figure out whether WoL is
> enabled or not. Only the parent has the full picture.

Hi Heiner

I think you need to look at your different runtime PM domains.  If i
understand the code right, you runtime suspend if there is no
link. But for this to work correctly, your PHY needs to keep working.
You also cannot assume all accesses to the PHY go via the MAC. Some
calls will go direct to the PHY, and they can trigger MDIO bus
accesses.  So i think you need two runtime PM domains. MAC and MDIO
bus.  Maybe just the pll? An MDIO bus is a device, so it can have its
on PM callbacks. It is not clear what you need to resume in order to
make MDIO work.

It might also help if you do the phy_connect in .ndo_open and
disconnect in .ndo_stop. This is a common pattern in drivers. But some
also do it is probe and remove.

     Andrew