netdev - Re: [PATCH 1/6] ravb: remove custom .nway

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: <20180524172331.GA2460@lunn.ch>
Date:   Thu, 24 May 2018 19:23:31 +0200
From:   Andrew Lunn <andrew@...n.ch>
To:     Sergei Shtylyov <sergei.shtylyov@...entembedded.com>
Cc:     Vladimir Zapolskiy <vz@...ia.com>,
        Vladimir Zapolskiy <vladimir_zapolskiy@...tor.com>,
        "David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org,
        linux-renesas-soc@...r.kernel.org
Subject: Re: [PATCH 1/6] ravb: remove custom .nway_reset from ethtool ops

> > For it to be unsafe, i think that would mean phylib would need to call
> > back into the MAC driver? The only way that could happen is via the
> > adjust_link call. And that will deadlock, since it takes the same
> > lock.
> > 
> > Or am i/we missing something?
> 
>    It doesn't take any locks currently, only patches #3/#6 makes it do so...

Ah, yes.

You should not be holding any spinlocks when calling into phylib.
It does its own locking, which is mutex based.

The code in this patch is not touching the MAC, so looks safe to me.

    Andrew