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Date: Sun, 16 Feb 2003 11:17:11 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: "Martin J. Bligh" <mbligh@aracnet.com>
cc: Anton Blanchard <anton@samba.org>, Andrew Morton <akpm@digeo.com>,
       Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Zwane Mwaikambo <zwane@holomorphy.com>,
       Manfred Spraul <manfred@colorfullife.com>
Subject: Re: Fw: 2.5.61 oops running SDET
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On Sun, 16 Feb 2003, Martin J. Bligh wrote:
> 
> Well, I did the stupid safe thing, and it hangs the box once we get up to 
> a load of 32 with SDET. Below is what I did, the only other issue I can
> see in here is that task_mem takes mm->mmap_sem which is now nested inside
> the task_lock inside tasklist_lock ... but I can't see anywhere that's a
> problem from a quick search

Ho - you can _never_ nest a semaphore inside a spinlock - if the semaphore 
sleeps, the spinlock will cause a lockup regardless of any reverse nesting 
issues.. So I guess the old "get_task_mm()" code is requried anyway.

		Linus

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