From 3ef0f720e47e895b613b0305eb0a483e3ec11f23 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@suse.cz>
Date: Wed, 14 May 2008 16:05:37 -0700
Subject: [PATCH] mm: fix infinite loop in filemap_fault

filemap_fault will go into an infinite loop if ->readpage() fails
asynchronously.

AFAICS the bug was introduced by this commit, which removed the wait after the
final readpage:

   commit d00806b183152af6d24f46f0c33f14162ca1262a
   Author: Nick Piggin <npiggin@suse.de>
   Date:   Thu Jul 19 01:46:57 2007 -0700

       mm: fix fault vs invalidate race for linear mappings

Fix by reintroducing the wait_on_page_locked() after ->readpage() to make sure
the page is up-to-date before jumping back to the beginning of the function.

I've noticed this while testing nfs exporting on fuse.  The patch
fixes it.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
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