linux-kernel - Re: [PATCH] Configure out doublefault exception handler (Linux Tiny)

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:	Fri, 15 Feb 2008 11:02:16 -0600
From:	Matt Mackall <mpm@...enic.com>
To:	Andi Kleen <andi@...stfloor.org>
Cc:	Thomas Petazzoni <thomas.petazzoni@...e-electrons.com>,
	Sam Ravnborg <sam@...nborg.org>, Linux-tiny@...enic.com,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, "H. Anvin" <hpa@...or.com>,
	Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH] Configure out doublefault exception handler (Linux
	Tiny)


On Fri, 2008-02-15 at 13:00 +0100, Andi Kleen wrote:
> Matt Mackall <mpm@...enic.com> writes:
> >
> > I bet there's some doublefault-handling code hiding somewhere. It's not
> > the sort of thing it'd make sense to take out of the architecture.
> 
> The big question is if it makes sense taking out of a kernel at all.
> I still think the answer is no.
> 
> Or have you considered replacing die() and show_trace() etc. with a single
> panic("the tiny gods say this won't happen") yet? That would be roughly 
> equivalent.

It's not a matter of "won't happen" so much as "not a damn thing we can
do when it does". There's very little point in having this sort of code
in a mass-market camera, phone, DVR, TV, etc. (of which there are
already millions running Linux). These devices have no console and
basically zero serviceability beyond firmware upgrades. If taking these
vestigial debugging features out means we can cram in more features that
consumers can actually see and will pay for, that's precisely what's
going to happen.

-- 
Mathematics is the supreme nostalgia of our time.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/