netdev - Re: [PATCH net-next 03/10] devlink: Serialize access to rate domains

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] [day] [month] [year] [list]

Message-ID: <wgbtvsogtf4wgxyz7q4i6etcvlvk6oi3xyckie2f7mwb3gyrl4@m7ybivypoojl>
Date: Wed, 26 Feb 2025 15:44:35 +0100
From: Jiri Pirko <jiri@...nulli.us>
To: Jakub Kicinski <kuba@...nel.org>
Cc: Tariq Toukan <tariqt@...dia.com>, 
	"David S. Miller" <davem@...emloft.net>, Paolo Abeni <pabeni@...hat.com>, 
	Eric Dumazet <edumazet@...gle.com>, Andrew Lunn <andrew+netdev@...n.ch>, 
	Jiri Pirko <jiri@...dia.com>, Cosmin Ratiu <cratiu@...dia.com>, 
	Carolina Jubran <cjubran@...dia.com>, Gal Pressman <gal@...dia.com>, Mark Bloch <mbloch@...dia.com>, 
	Donald Hunter <donald.hunter@...il.com>, Jonathan Corbet <corbet@....net>, 
	Saeed Mahameed <saeedm@...dia.com>, Leon Romanovsky <leon@...nel.org>, netdev@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-doc@...r.kernel.org, linux-rdma@...r.kernel.org
Subject: Re: [PATCH net-next 03/10] devlink: Serialize access to rate domains

Wed, Feb 26, 2025 at 02:40:05AM +0100, kuba@...nel.org wrote:
>On Tue, 25 Feb 2025 14:36:07 +0100 Jiri Pirko wrote:
>> >The problem comes from having a devlink instance per function /
>> >port rather than for the ASIC. Spawn a single instance and the
>> >problem will go away 🤷️  
>> 
>> Yeah, we currently have VF devlink ports created under PF devlink instance.
>> That is aligned with PCI geometry. If we have a single per-ASIC parent
>> devlink, this does not change and we still need to configure cross
>> PF devlink instances.
>
>Why would there still be PF instances? I'm not suggesting that you
>create a hierarchy of instances.

I'm not sure how you imagine getting rid of them. One PCI PF
instantiates one devlink now. There are lots of configuration (e.g. params)
that is per-PF. You need this instance for that, how else would you do
per-PF things on shared ASIC instance?
Creating SFs is per-PF operation for example. I didn't to thorough
analysis, but I'm sure there are couple of per-PF things like these.
Also not breaking the existing users may be an argument to keep per-PF
instances.

>
>> The only benefit I see is that we don't need rate domain, but
>> we can use parent devlink instance lock instead. The locking ordering
>> might be a bit tricky to fix though.