linux-kernel - Re: [PATCH 2/2] net: ethernet: bcmgenet: use phy_ethtool_{get|set}_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: <1467754810.4204.17.camel@decadent.org.uk>
Date:	Tue, 05 Jul 2016 23:40:10 +0200
From:	Ben Hutchings <ben@...adent.org.uk>
To:	Florian Fainelli <f.fainelli@...il.com>,
	Philippe Reynes <tremyfr@...il.com>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] net: ethernet: bcmgenet: use
 phy_ethtool_{get|set}_link_ksettings

On Tue, 2016-07-05 at 14:15 -0700, Florian Fainelli wrote:
> On 07/05/2016 02:07 PM, Philippe Reynes wrote:
> > Hi Florian,
> > 
> > On 05/07/16 06:30, Florian Fainelli wrote:
> > > Le 04/07/2016 16:03, David Miller a écrit :
> > > > From: Philippe Reynes<tremyfr@...il.com>
> > > > Date: Sun,  3 Jul 2016 17:33:57 +0200
> > > > 
> > > > > There are two generics functions phy_ethtool_{get|set}_link_ksettings,
> > > > > so we can use them instead of defining the same code in the driver.
> > > > > 
> > > > > Signed-off-by: Philippe Reynes<tremyfr@...il.com>
> > > > 
> > > > Applied.
> > > > 
> > > 
> > > The transformation is not equivalent, we lost the checks on
> > > netif_running() in the process, and those are here for a reason, if the
> > > interface is down and therefore clock gated, MDIO accesses to the PHY
> > > will simply fail outright and cause bus errors.
> > 
> > Oh, I see, I've missed this. Sorry for this mistake.
> > We should revert this path.
> 
> Well, maybe better than that, actually put the check in the generic
> functions, because if the link is down, aka netif_running() returns
> false, link parameters cannot be reliably queried and they are invalid.

Either the hardware or the driver needs to remember:

- Is auto-negotiation enabled
- If so, which modes are advertised
- If not, which mode is forced

And it should still be possible to get or set that information when the
interface is down.

Ben.

-- 

Ben Hutchings
Life is what happens to you while you're busy making other plans.
                                                               - John
Lennon

Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)