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Date: Wed, 19 Oct 2005 09:47:57 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: Andrew Morton <akpm@osdl.org>
Cc: linux-kernel@vger.kernel.org, mason@suse.com
Subject: Re: [PATCH] fix nr_unused accounting, and avoid recursing in iput with I_WILL_FREE set
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On Tue, Oct 18, 2005 at 05:13:35PM -0700, Andrew Morton wrote:
> Well according to my assertion (below), the inode in __sync_single_inode()
> cannot have a zero refcount, so the whole if() statement is never executed.

It can, but only if it comes from I_WILL_FREE path
(generic_forget_inode).  See the write_inode_now in
generic_forget_inode.

My BUG_ON already makes sure that when i_count is zero, I_WILL_FREE is
set (I_WILL_FREE will prevent the inode to be freed by the vm as well,
so it's ok).