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From: "Luck, Tony" <tony.luck@intel.com>
To: Andy Lutomirski <luto@amacapital.net>, Benjamin Herrenschmidt
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Date: Mon, 6 Jul 2015 19:11:22 +0000
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Subject: Re: [Ksummit-discuss] [TECH TOPIC] Semantics of MMIO mapping
 attributes accross archs
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>> Another side topic that has come up in this space is the desire to
>> define a "memremap" api to clean up __iomem abuses for cases where
>> "memory-like" mappings are needed.
>>
>> https://lkml.org/lkml/2015/6/22/100
>
> Interesting. I had missed this. There is a similar question about
> semantics (ordering etc...), ie, are they the same as memory for
> example ?

The drivers/acpi/apei/* usages are just mapping bits of normal memory that
happens to be BIOS reserved.  ioremap*() got used because it was available
and did the right thing with the page tables even though it broke the __iom=
em
annotations.  memremap() sounds like a great idea for these.

-Tony