netdev - Re: [PATCH v2 net-next] net: phy: improve pause handling

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: <20190501203550.GH19809@lunn.ch>
Date:   Wed, 1 May 2019 22:35:50 +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 v2 net-next] net: phy: improve pause handling

On Wed, May 01, 2019 at 09:34:43PM +0200, Heiner Kallweit wrote:
> When probing the phy device we set sym and asym pause in the "supported"
> bitmap (unless the PHY tells us otherwise). However we don't know yet
> whether the MAC supports pause. Simply copying phy->supported to
> phy->advertising will trigger advertising pause, and that's not
> what we want. Therefore add phy_advertise_supported() that copies all
> modes but doesn't touch the pause bits.
> 
> In phy_support_(a)sym_pause we shouldn't set any bits in the supported
> bitmap because we may set a bit the PHY intentionally disabled.
> Effective pause support should be the AND-combined PHY and MAC pause
> capabilities. If the MAC supports everything, then it's only relevant
> what the PHY supports. If MAC supports sym pause only, then we have to
> clear the asym bit in phydev->supported.
> Copy the pause flags only and don't touch the modes, because a driver
> may have intentionally removed a mode from phydev->advertising.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@...il.com>

Reviewed-by: Andrew Lunn <andrew@...n.ch>

    Andrew