netdev - Re: [PATCH net-next] net: skbuff: Skip early return in skb

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: <20240730071033.24c9127c@kernel.org>
Date: Tue, 30 Jul 2024 07:10:33 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: Paolo Abeni <pabeni@...hat.com>
Cc: Florian Westphal <fw@...len.de>, Breno Leitao <leitao@...ian.org>,
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet
 <edumazet@...gle.com>, leit@...a.com, Chris Mason <clm@...com>, "open
 list:NETWORKING DRIVERS" <netdev@...r.kernel.org>, open list
 <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH net-next] net: skbuff: Skip early return in skb_unref
 when debugging

On Tue, 30 Jul 2024 13:15:57 +0200 Paolo Abeni wrote:
> > If thats the case why does it exist at all?

+1

> > I was under impression that entire reason for CONFIG_DEBUG_NET was
> > to enable more checks for fuzzers and the like, i.e. NOT for production
> > kernels.  
> 
> I feel like I already had this discussion and I forgot the outcome, if 
> so I'm sorry. To me the "but is safe to select." part in the knob 
> description means this could be enabled in production, and AFAICS the 
> CONFIG_DEBUG_NET-enabled code so far respects that assumption.

I believe the previous discussion was page pool specific and there
wasn't as much of a conclusion as an acquiescence (read: we had more
important things on our minds than that argument ;)).

Should we set a bar for how much perf impact is okay?

FTR I suspect there will be no measurable perf impact here.