From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PROBLEM] WARNING: at kernel/exit.c:910 do_exit
Date: Sun, 21 Nov 2010 20:29:53 +0100
Message-ID: <20101121192953.GA4495@redhat.com>
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Cc: Jens Axboe <jaxboe@fusionio.com>,
	Pekka Enberg <penberg@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux Netdev List <netdev@vger.kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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On 11/21, Linus Torvalds wrote:
>
> I do wonder if we should just flag a thread as "busy oopsing" before
> we call "do_exit(), so that _if_ we do a recursive oops we
>
>  (a) don't print it out (except just a one-liner to say "recursively
> oopsed in %pS" or something)
>  (b) don't try to clean up with do_exit (because that's likely just
> going to oops again or run out of stack etc)
>
> That might have left us with a more visible original oops. Maybe the
> register contents at that point could have given us any ideas (ie
> things like the slab poisoning memory patterns or whatever).

+inf ;)

I thought about this many times. To me, the major offender is
__schedule_bug(). It is quite useful by itself, but every bug with
spinlock held triggers it.

Oleg.