linux-kernel - Re: BUG_ON() in workingset_node_shadows

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]

Date:   Wed, 5 Oct 2016 23:09:00 +0200
From:   Willy Tarreau <w@....eu>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     Paul Gortmaker <paul.gortmaker@...driver.com>,
        Johannes Weiner <hannes@...xchg.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Antonio SJ Musumeci <trapexit@...wn.link>,
        Miklos Szeredi <miklos@...redi.hu>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        stable <stable@...r.kernel.org>
Subject: Re: BUG_ON() in workingset_node_shadows_dec() triggers

On Wed, Oct 05, 2016 at 12:18:51PM -0700, Linus Torvalds wrote:
> Quite frankly, I wouldn't do a sed-script pass to actually change
> existing users. I'd just change how the BUG() implementation itself
> works. Not make it a direct WARN_ON(), but perhaps something like
> 
>  - use WARN_ON() with a global rate limiter (we do *not* want BUG
> cascades, but re-enable the warning after a few minutes)

That's interesting, I had exactly this discussion at kernel recipes
last week with someone complaining that when warnings scroll, you
only see the last ones while only the first one is useful. I guess
in most situations we don't even need a rate limiter, just print a
single dump and wait 2 minutes or so for the person in front of the
screen to have the time to take a photo.

>  - have some kernel command line option for the server people to allow
> them to just force a reboot for it

Good point for not doing the sed.

> Hmm?
> 
> Anybody want to play with it?

Many people will be much more efficient than me at doing it and even
testing it so I won't volunteer here.

Willy