On Tue, 12 Nov 2002, David S. Miller wrote:
> From: Hugh Dickins <hugh@veritas.com>
> Date: Tue, 12 Nov 2002 17:43:40 +0000 (GMT)
>
> Sorry, I still don't get it. If the flush_cache_page is doing something
> necessary, then won't a user access in between it and invalidating pte
> undo what was necessary? And if it's not necessary, why do we do it?
> (For better performance would be a very good reason.)
>
> If there are other writable mappings of the page, we can't swap
> it out legally.
But I'm worried about the case where this is the last writable mapping:
it seems userspace (on another CPU) can still write to it in between
the flush_cache_page and invalidation of the pte (on this CPU hoping
to swap out that page).
Hugh
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Nov 15 2002 - 22:00:27 EST