linux-kernel - Re: BUG-lockdep and freeze (was: Arrr! Linux 2.6.18)

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:	Sun, 1 Oct 2006 01:56:52 +0200
From:	Andi Kleen <ak@...e.de>
To:	Linus Torvalds <torvalds@...l.org>
Cc:	Eric Rannaud <eric.rannaud@...il.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>, Andrew Morton <akpm@...l.org>,
	nagar@...son.ibm.com, Chandra Seetharaman <sekharan@...ibm.com>,
	Jan Beulich <jbeulich@...ell.com>
Subject: Re: BUG-lockdep and freeze (was: Arrr! Linux 2.6.18)

On Sunday 01 October 2006 00:55, Linus Torvalds wrote:
> 
> On Sun, 1 Oct 2006, Andi Kleen wrote:
> > 
> > No, it's not. On x86-64 it can be three or more stacks nested in
> > complicated ways (process stack, interrupt stack, exception stack)
> > The exception stack can happen multiple times.
> 
> And you don't think that's true on x86?

On i386 it is simpler (only one interrupt stack and one process stack)
However there can be still nasty corner cases, like the temporary NMI stacks
that were added recently. It could be probably all handled in a state machine,
but it would be ugly (at least I heard complaints about the x86 code that
does it) 
 
> Read the x86 code. Please. The one _before_ you added unwinding.

It's still the same if you disable unwinding.

-Andi
-
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/