From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@redhat.com>
Subject: Re: [PACTH][IPV6] Introduce ip6_append_data
Date: Wed, 16 Apr 2003 21:03:06 -0700 (PDT)
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You take direct page_address() of page, this is in general illegal.

Generally you must kmap the page to access it in the kernel as it may
be a HIGHMEM page.

I know that right now you control all the allocations with
alloc_page() and sk->allocation cannot currently allow highmem pages,
but let us not start with the assumptions right now :-)

As soon as you write udp6_sendfile() you will need to handle
this, that is for sure.