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Subject: Re: [PATCH] BUG(): sched.c: Line 944
From: Robert Love <rml@tech9.net>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: linux-kernel@vger.kernel.org
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Date: 16 Sep 2002 19:58:09 -0400
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On Mon, 2002-09-16 at 19:45, Linus Torvalds wrote:

> Ahhah! I know. You just make lock_depth 0 when you exit, without actually 
> taking the kernel lock. Which fools the logic into accepting a 
> preempt-disable, since it thinks that the preempt disable is due to 
> holding the kernel lock.

I was this -> <- close to celebrating.  Not so fast, smarty.

What about release_kernel_lock() ?

It sees task->lock_depth>=0 and calls spin_unlock() on a lock that it
does not hold.

	Robert Love

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