netdev - Re: [RFC PATCH net-next] net: sched: flower: refactor reoffload for concurrent access

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: <vbfftqfurep.fsf@mellanox.com>
Date:   Thu, 18 Apr 2019 17:58:26 +0000
From:   Vlad Buslov <vladbu@...lanox.com>
To:     Jakub Kicinski <jakub.kicinski@...ronome.com>
CC:     Vlad Buslov <vladbu@...lanox.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "jhs@...atatu.com" <jhs@...atatu.com>,
        "xiyou.wangcong@...il.com" <xiyou.wangcong@...il.com>,
        "jiri@...nulli.us" <jiri@...nulli.us>,
        "davem@...emloft.net" <davem@...emloft.net>
Subject: Re: [RFC PATCH net-next] net: sched: flower: refactor reoffload for
 concurrent access


On Thu 18 Apr 2019 at 20:46, Jakub Kicinski <jakub.kicinski@...ronome.com> wrote:
> On Thu, 18 Apr 2019 16:33:22 +0000, Vlad Buslov wrote:
>> Considering this, I tried to improve my solution to remove possibility
>> of multiple adds of same filter and it seems to me that it would be
>> enough to move hw_filters list management in flower offloads functions:
>> add filter to list while holding rtnl lock in fl_hw_replace_filter() and
>> remove it from list while holding rtnl lock in fl_hw_destroy_filter().
>> What do you think?
>
> Sounds good for now, but I presume the plan is to get rid of rtnl
> around the driver call.. at which point we would switch to a rwlock? :)

Yes, but I would like the lock to be in cls hw offloads API
(tc_setup_cb_replace(), etc) and not in flower itself. That would also
solve deadlock issue and make code reusable for any further unlocked
classifiers implementations.