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Date:   Wed, 21 Jun 2023 11:15:41 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Michael Roth <michael.roth@amd.com>, kvm@vger.kernel.org,
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Subject: Re: [PATCH RFC v9 07/51] x86/sev: Add the host SEV-SNP
 initialization support
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References: <20230612042559.375660-1-michael.roth@amd.com>
 <20230612042559.375660-8-michael.roth@amd.com>
 <12f95b38-427c-6810-373a-ba2062c43882@intel.com>
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On Mon, Jun 12, 2023 at 08:34:02AM -0700, Dave Hansen wrote:
> On 6/11/23 21:25, Michael Roth wrote:
> > +	/*
> > +	 * Calculate the amount the memory that must be reserved by the BIOS to
> > +	 * address the whole RAM, including the bookkeeping area. The RMP itself
> > +	 * must also be covered.
> > +	 */
> > +	max_rmp_pfn = max_pfn;
> > +	if (PHYS_PFN(rmp_end) > max_pfn)
> > +		max_rmp_pfn = PHYS_PFN(rmp_end);
> 
> Could you say a little here about how this deals with memory hotplug?

Does SNP hw even support memory hotplug?

I think in order to support that, you'd need some special dance because
of the RMP table etc...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette