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Date:   Tue, 20 Dec 2022 10:55:44 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Chao Peng <chao.p.peng@linux.intel.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v10 3/9] KVM: Extend the memslot to support fd-based
 private memory
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References: <20221202061347.1070246-1-chao.p.peng@linux.intel.com>
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 <20221220074318.GC1724933@chaop.bj.intel.com>
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On Tue, Dec 20, 2022 at 03:43:18PM +0800, Chao Peng wrote:
> RESTRICTEDMEM is needed by TDX_HOST, not TDX_GUEST.

Which basically means that RESTRICTEDMEM should simply depend on KVM.
Because you can't know upfront whether KVM will run a TDX guest or a SNP
guest and so on.

Which then means that RESTRICTEDMEM will practically end up always
enabled in KVM HV configs.

> The only reason to add another HAVE_KVM_RESTRICTED_MEM is some code only
> works for 64bit[*] and CONFIG_RESTRICTEDMEM is not sufficient to enforce
> that.

This is what I mean with "we have too many Kconfig items". :-\

-- 
Regards/Gruss,
    Boris.

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