linux-kernel - Re: [Issue report] drivers/ftgmac100: DHCP occasionally fails during boot up or link down/up

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]

Date:   Sat, 19 Feb 2022 19:28:18 +0100
From:   Andrew Lunn <andrew@...n.ch>
To:     Heyi Guo <guoheyi@...ux.alibaba.com>
Cc:     "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Joel Stanley <joel@....id.au>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Dylan Hung <dylan_hung@...eedtech.com>, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [Issue report] drivers/ftgmac100: DHCP occasionally fails during
 boot up or link down/up

On Sat, Feb 19, 2022 at 06:08:35PM +0800, Heyi Guo wrote:
> Hi Andrew,
> 
> The DHCP issue is gone after applying below patch. I put the lock statements
> outside of the pure reset function, for the phydev lock has been acquired
> before calling adjust_link. The lock order in ftgmac100_reset_task() was
> also changed, to make it the same as the lock procedure in adjust_link, in
> which the phydev is locked first and then rtnl_lock. I'm not quite sure
> whether it will bring in any potential dead lock. Any advice?

Did you run the code with CONFIG_PROVE_LOCKING enabled. That will help
detect possible deadlock situations.

       Andrew