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Date:   Sat, 03 Sep 2022 08:31:09 +0000
From:   Boris Petkov <bp@alien8.de>
To:     "Kalra, Ashish" <Ashish.Kalra@amd.com>
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Subject: =?US-ASCII?Q?RE=3A_=5BPATCH_Part2_v6_09/49=5D_x86/fault=3A_Add_sup?= =?US-ASCII?Q?port_to_handle_the_RMP_fault_for_user_address?=
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On September 3, 2022 6:57:51 AM UTC, "Kalra, Ashish" <Ashish=2EKalra@amd=2E=
com> wrote:
>[AMD Official Use Only - General]
>
>So essentially we want to map the faulting address to a RMP entry, consid=
ering the fact that a 2M host hugepage can be mapped as=20
>4K RMP table entries and 1G host hugepage can be mapped as 2M RMP table e=
ntries=2E

So something's seriously confusing or missing here because if you fault on=
 a 2M host page and the underlying RMP entries are 4K then you can use pte_=
index()=2E

If the host page is 1G and the underlying RMP entries are 2M, pmd_index() =
should work here too=2E

But this piecemeal back'n'forth doesn't seem to resolve this so I'd like t=
o ask you pls to sit down, take your time and give a detailed example of th=
e two possible cases and what the difference is between pte_/pmd_index and =
your way=2E Feel free to add actual debug output and paste it here=2E

Thanks=2E

--=20
Sent from a small device: formatting sux and brevity is inevitable=2E