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Date:   Tue, 24 Nov 2020 10:00:55 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc:     Ashish Kalra <Ashish.Kalra@amd.com>, hch@lst.de,
        tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
        x86@kernel.org, luto@kernel.org, peterz@infradead.org,
        dave.hansen@linux-intel.com, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, brijesh.singh@amd.com,
        Thomas.Lendacky@amd.com, jon.grimm@amd.com, rientjes@google.com
Subject: Re: [PATCH v6] swiotlb: Adjust SWIOTBL bounce buffer size for SEV
 guests.
Message-ID: <20201124090055.GB4009@zn.tnic>
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 <20201123175632.GA21539@char.us.oracle.com>
 <20201123180215.GG15044@zn.tnic>
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On Mon, Nov 23, 2020 at 01:43:27PM -0500, Konrad Rzeszutek Wilk wrote:
> I am assuming that TDX is going to have the same exact issue that 
> AMD SEV will have.
> 
> Are you recommending to have an unified x86 specific callback
> where we check if it:
> 
>  - CPUID_AMD_SEV or CPUID_INTEL_TDX is set, and
>  - No vIOMMU present, then we adjust the size?

I'm thinking do it correct right now and when TDX appears on the horizon
requesting this adjusted to TDX, then change it. Like we always do.

-- 
Regards/Gruss,
    Boris.

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