netdev - Re: [PATCH net-next 1/5] bnxt: use the devlink instance lock to protect sriov

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: <20220317111959.7cad8fb1@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Thu, 17 Mar 2022 11:19:59 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Sriharsha Basavapatna <sriharsha.basavapatna@...adcom.com>
Cc:     netdev@...r.kernel.org,
        Jiří Pírko <jiri@...nulli.us>,
        leonro@...dia.com, saeedm@...dia.com, idosch@...sch.org,
        Michael Chan <michael.chan@...adcom.com>,
        simon.horman@...igine.com
Subject: Re: [PATCH net-next 1/5] bnxt: use the devlink instance lock to
 protect sriov

On Thu, 17 Mar 2022 23:15:33 +0530 Sriharsha Basavapatna wrote:
> The changes look good to me overall. But I have a few concerns. This
> change introduces a lock that is held across modules and if there's
> any upcall from the driver into devlink that might potentially acquire
> the same lock, then it could result in a deadlock. I'm not familiar
> with the internals of devlink, but just want to make sure this point
> is considered. Also, the driver needs to be aware of this lock and use
> it in new code paths within the driver to synchronize with switchdev
> operations. This may not be so obvious when compared to a driver
> private lock.

That's true, that's why we're adding the new "unlocked" devl_* API.
I'm switching the drivers accordingly, I didn't see any upcalls in 
the relevant parts in bnxt, LMK if I missed something!