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Date:   Wed, 17 Jul 2019 09:41:24 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     jglisse@redhat.com, ebaskakov@nvidia.com, jhubbard@nvidia.com,
        mhairgrove@nvidia.com, SCheung@nvidia.com, sgutti@nvidia.com,
        aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com,
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        paulmck@linux.vnet.ibm.com, ross.zwisler@linux.intel.com,
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        kernel list <linux-kernel@vger.kernel.org>
Subject: HMM_MIRROR has less than useful help text
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Hi!

Commit c0b124054f9e42eb6da545a10fe9122a7d7c3f72 has very nice commit
message, explaining what HMM_MIRROR is and when it is
needed. Unfortunately, it did not make it into Kconfig help:

CONFIG_HMM_MIRROR:

Select HMM_MIRROR if you want to mirror range of the CPU page table of
a
process into a device page table. Here, mirror means "keep
synchronized".
Prerequisites: the device must provide the ability to write-protect
its
page tables (at PAGE_SIZE granularity), and must be able to recover
=66rom
the resulting potential page faults.

Could that be fixed?

This is key information for me:

# This is a heterogeneous memory management (HMM) process address space
# mirroring.
# This is useful for NVidia GPU >=3D Pascal, Mellanox IB >=3D mlx5 and more
# hardware in the future.

Thanks,
								Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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