linux-kernel - Re: [PATCH] firmware: dmi_scan: Drop dmi

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: <20170925092644.7teso4xhkjw2hksl@hirez.programming.kicks-ass.net>
Date:   Mon, 25 Sep 2017 11:26:44 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Jean Delvare <jdelvare@...e.de>
Cc:     Ingo Molnar <mingo@...nel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH] firmware: dmi_scan: Drop dmi_initialized

On Mon, Sep 25, 2017 at 11:00:11AM +0200, Jean Delvare wrote:
> Then we have that in common. While reading the code and its history, I
> was worried that the justification to add this warning in the first
> place was technically weak. Not every coding error must automatically
> translate to a patch to make the code robust against said error.
> Sometimes you just have to admit that you did not pay attention as you
> should have, fix your mistake, possibly document it for others, and
> move on. Otherwise we end up with slow bloated code.

That WARN_ON() is a form of documentation.

And if you care about performance for your code path, hide it under some
CONFIG_*_DEBUG, but in general WARN_ON() isn't terribly expensive
(depending entirely on the complexity of the condition of course).