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To:     =?iso-8859-15?Q?Michal_Koutn=FD?= <mkoutny@suse.com>
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Subject: Re: [PATCH v5 12/18] x86/sgx: Add EPC OOM path to forcefully reclaim
 EPC
References: <op.2clydbf8wjvjmi@hhuan26-mobl.amr.corp.intel.com>
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 <op.2cxmq7c2wjvjmi@hhuan26-mobl.amr.corp.intel.com>
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Date:   Tue, 17 Oct 2023 23:39:27 -0500
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From:   "Haitao Huang" <haitao.huang@linux.intel.com>
Organization: Intel
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On Tue, 17 Oct 2023 14:13:22 -0500, Michal Koutn=FD <mkoutny@suse.com> w=
rote:

> On Tue, Oct 17, 2023 at 08:54:48PM +0200, Michal Koutn=FD  =

> <mkoutny@suse.com> wrote:
>> Is this distinction between preemptability of EPC pages mandated by t=
he
>> HW implementation? (host/"process" enclaves vs VM enclaves) Or do hav=
e
>> users an option to lock certain pages in memory that yields this
>> difference?
>
> (After skimming Documentation/arch/x86/sgx.rst, Section "Virtual EPC")=

>
> Or would these two types warrant also two types of miscresource? (To
> deal with each in own way.)

They are from the same bucket of HW resource so I think it's more suitab=
le  =

to be one resource type. Otherwise need to policy to dividing the  =

capacity, etc. And it is still possible in future vEPC become reclaimabl=
e.

My current thinking is we probably can get away with non-preemptive  =

max_write for enclaves too. See my other reply.

Thanks
Haitao