On Fri, 13 Jun 2008 10:44:44 +0900, KAMEZAWA Hiroyuki said:

quoted text
> quick fix for double unlock_page();
> 
> Signed-off-by: KAMEZAWA Hiroyuki <kamewzawa.hiroyu@jp.fujitsu.com>
> Index: linux-2.6.26-rc5-mm3/mm/truncate.c
> ===================================================================
> --- linux-2.6.26-rc5-mm3.orig/mm/truncate.c
> +++ linux-2.6.26-rc5-mm3/mm/truncate.c
> @@ -104,8 +104,8 @@ truncate_complete_page(struct address_sp
>  
>  	cancel_dirty_page(page, PAGE_CACHE_SIZE);
>  
> -	remove_from_page_cache(page);
>  	clear_page_mlock(page);
> +	remove_from_page_cache(page);
>  	ClearPageUptodate(page);
>  	ClearPageMappedToDisk(page);
>  	page_cache_release(page);	/* pagecache ref */

Confirming this quick fix works on my laptop that was hitting this crash -
am now up and running on -rc5-mm3.