From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Piggin <npiggin@suse.de>
Subject: Re: [patch 9/9] mm: fix pagecache write deadlocks
Date: Mon, 29 Jan 2007 12:11:15 +0100
Message-ID: <20070129111115.GA14504@wotan.suse.de>
References: <20070129081905.23584.97878.sendpatchset@linux.site> <20070129082030.23584.72376.sendpatchset@linux.site>
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On Mon, Jan 29, 2007 at 11:33:03AM +0100, Nick Piggin wrote:
> +		} else {
> +			char *src, *dst;
> +			src = kmap(src_page);
> +			dst = kmap(page);
> +			memcpy(dst + offset,
> +				src + ((unsigned long)buf & ~PAGE_CACHE_MASK),
> +				bytes);
> +			kunmap(page);
> +			kunmap(src_page);
> +			copied = bytes;
> +		}
>  		flush_dcache_page(page);

Hmm, I guess these should use kmap_atomic with KM_USER[01]?

The kmap is from an earlier iteration that wanted to sleep
with the page mapped into kernel.