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Subject: Re: [PATCH 0/7] ACPI HMAT memory sysfs representation
References: <20181114224902.12082-1-keith.busch@intel.com>
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Mon, 26 Nov 2018 08:42:23 -0800
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To: Dan Williams <dan.j.williams@intel.com>
Cc: anshuman.khandual@arm.com, Keith Busch <keith.busch@intel.com>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Linux ACPI <linux-acpi@vger.kernel.org>, Linux MM <linux-mm@kvack.org>, Greg KH <gregkh@linuxfoundation.org>, "Rafael J. Wysocki" <rafael@kernel.org>

On 11/23/18 1:13 PM, Dan Williams wrote:
>> A new system call makes total sense to me.  I have the same concern
>> about the completeness of what's exposed in sysfs, I just don't see a
>> _route_ to completeness with sysfs itself.  Thus, the minimalist
>> approach as a first step.
> Outside of platform-firmware-id to Linux-numa-node-id what other
> userspace API infrastructure does the kernel need to provide? It seems
> userspace enumeration of memory attributes is fully enabled once the
> firmware-to-Linux identification is established.

It would be nice not to have each app need to know about each specific
platform's firmware.