linux-kernel - Re: lockdep and oops_in

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:	Thu, 05 Aug 2010 10:10:49 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Dave Airlie <airlied@...il.com>
Cc:	Ingo Molnar <mingo@...hat.com>,
	Jesse Barnes <jbarnes@...tuousgeek.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: lockdep and oops_in_progress

On Thu, 2010-08-05 at 16:21 +1000, Dave Airlie wrote:
> Hi guys,
> 
> I was debugging a wierd issue with suspend/resume and fbcon/X with
> some recent work Jesse and myself did to try and make sure a pinned
> fbcon always gets the text on it with a panic or oops occurs.
> 
> It does this by testing the oops_in_progress flag, however once any
> lockdep issue occurs it looks to me that we leave this flag set
> forever, in most places I can see in oops code etc they call
> bust_spinlocks(1) then bust_spinlocks(0) to balance the
> oops_in_progress value, but lockdep never seems to reset it.
> 
> I'm wondering if there is an inherent reason for this or if I whip up
> a patch to reset once the lockdep is printed if this would cause any
> issues?

That's debug_locks_off(), right? I don't think there's a particular
reason we keep it set, cleaning that up might take a bit of work but
shouldn't be too hard.

Ingo, do you remember anything about that?, I think that bit comes from
before my 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/