Re: [RFC][patch 0/2] mm: remove PageReserved

Nick Piggin
2005-08-09T10:27:32Z

Hugh Dickins wrote:

>
> You're right (though I imagine might sometimes be holes rather than RAM).
>

Yep. These holes are what I have in mind, and random other things
like the !(bad_ppro && page_kills_ppro(pfn)) check.

[...]

> I think Nick is treating the "use" of PageReserved in ioremap much too
> reverentially. Fine to leave its removal from there to a later stage,
> but why shouldn't that also be removed?
>

Well, as far as I had been able to gather, ioremap is trying to
ensure it does indeed only hit one of these holes, and not valid
RAM. I thought the fact that it *won't* bail out when encountering
kernel text or remap_pfn_range'ed pages was only due to PG_reserved
being the proverbial jack of all trades, master of none.

I could be wrong here though.

But in either case: I agree that it is probably not a great loss
to remove the check, although considering it will be needed for
swsusp anyway...

--
SUSE Labs, Novell Inc.

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