From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: start_kernel(): bug: interrupts were enabled early
Date: Thu, 01 Apr 2010 12:17:11 +1100
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To: Andrew Morton <akpm@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>, Christoph Lameter <cl@linux-foundation.org>, Matthew Wilcox <matthew@wil.cx>, Yinghai Lu <yinghai@kernel.org>, Rabin Vincent <rabin@rab.in>, lkml <linux-kernel@vger.kernel.org>, penberg@cs.helsinki.fi, linux-arch@vger.kernel.org

On Wed, 2010-03-31 at 15:49 -0700, Andrew Morton wrote:
> 
> But these things are all utterly gross.  The bottom line is that
> radix_tree_init() is manifestly unsuited to being called with local
> interrupts disabled.  773e3eb7b81e5ba13b5155dfb3bb75b8ce37f8f9 was
> just a wrong patch. 

Except that powerpc (and now it seems x86) both want to use radix trees
for interrupt handling... At least on powerpc, we trick and use a linear
search until the radix trees are initialized, which we do later during
boot, but that somewhat sucks.

I believe sherry picking things like not calling radix_tree_init() is
going to fix one case today, until we have another one, and another one,
and etc...

I suspect we're better off fixing the root of the problem in down/up.

Cheers,
Ben.