PFs on pages pinned with get_user_pages()

[Frank Mehnert]

Hi,

please could someone explain me under which circumstances a pagefault,
either generated from kernel code or from userland code, can occur on
pages which are pinned with get_user_pages()?

So far my understanding was that this can _never_ happen but I seems to
be wrong. Under high memory pressure I get PFs on such pages raised from
kernel code and the PFs are handled by do_swap_page(). When this happens,
page_count is 3 but page_mapped() returns false.

Thanks in advance,

Frank
-- 
Dr.-Ing. Frank Mehnert    Sun Microsystems    http://www.sun.com/

Attachment: signature.asc
Description: This is a digitally signed message part.