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Subject: Re: [PATCH] ppc64: Fix possible race with set_pte on a present PTE
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@osdl.org>
Cc: "David S. Miller" <davem@redhat.com>, wesolows@foobazco.org,
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Ok, your patch just missed the do_wp_page() case which needs the same
medication as break_cow(), which leaves us with only one caller of
ptep_establish... the one which just sets those 2 bits and shouldn't
be named ptep establish at all ;)

What do we do ?

I'd rather have ptep_establish do the ptep_clear_flush & set_pte, and
the later just do the bit flip, but then, the arch (and possibly
generic) implementation of that bit flip must also do the TLB flush
when necessary (it's not on ppc).

Ben.