netdev - Re: [PATCH net-next v10 14/22] io_uring/zcrx: grab a net device

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: <20250115191217.5ab89aa3@kernel.org>
Date: Wed, 15 Jan 2025 19:12:17 -0800
From: Jakub Kicinski <kuba@...nel.org>
To: Pavel Begunkov <asml.silence@...il.com>
Cc: David Wei <dw@...idwei.uk>, io-uring@...r.kernel.org,
 netdev@...r.kernel.org, Jens Axboe <axboe@...nel.dk>, Paolo Abeni
 <pabeni@...hat.com>, "David S. Miller" <davem@...emloft.net>, Eric Dumazet
 <edumazet@...gle.com>, Jesper Dangaard Brouer <hawk@...nel.org>, David
 Ahern <dsahern@...nel.org>, Mina Almasry <almasrymina@...gle.com>,
 Stanislav Fomichev <stfomichev@...il.com>, Joe Damato <jdamato@...tly.com>,
 Pedro Tammela <pctammela@...atatu.com>
Subject: Re: [PATCH net-next v10 14/22] io_uring/zcrx: grab a net device

On Thu, 16 Jan 2025 02:33:06 +0000 Pavel Begunkov wrote:
> On 1/16/25 01:06, Jakub Kicinski wrote:
> > On Wed,  8 Jan 2025 14:06:35 -0800 David Wei wrote:  
> >> From: Pavel Begunkov <asml.silence@...il.com>
> >>
> >> Zerocopy receive needs a net device to bind to its rx queue and dma map
> >> buffers. As a preparation to following patches, resolve a net device
> >> from the if_idx parameter with no functional changes otherwise.  
> > 
> > How do you know if someone unregisters this netdevice?
> > The unregister process waits for all the refs to be released,
> > for *ekhm* historic reasons. Normally ref holders subscribe
> > to netdev events and kill their dependent objects. Perhaps
> > it is somewhere else/later in the series...  
> 
> Ok, I can pin the struct device long term instead and kill
> netdev in the uninstall callback off
> unregister_netdevice_many_notify(), if that works with you.

I think that would work. You mean the "underlying" device, right,
netdev->dev.parent ? Like page_pool itself does. SG.