Date:   Thu, 23 Dec 2021 23:56:04 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Tom Lendacky <thomas.lendacky@amd.com>, tglx@linutronix.de,
        mingo@redhat.com, luto@kernel.org, peterz@infradead.org,
        sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com,
        ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com,
        hpa@zytor.com, jgross@suse.com, jmattson@google.com,
        joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org,
        pbonzini@redhat.com, sdeep@vmware.com, seanjc@google.com,
        tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 19/26] x86/tdx: Make pages shared in ioremap()
Message-ID: <20211223205604.g44kez5d7iedatfo@box.shutemov.name>
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On Thu, Dec 23, 2021 at 08:53:27PM +0100, Borislav Petkov wrote:
> On Thu, Dec 23, 2021 at 11:45:19AM -0800, Dave Hansen wrote:
> > CC_ATTR_SME_SOMETHING would get set when sme_me_mask is initialized to
> > something non-zero.  That will keep folks from falling into the same
> > trap that you did in the long term.
> 
> I guess CC_ATTR_MEM_ENCRYPT which basically says generic memory
> encryption...

Except CC_ATTR_MEM_ENCRYPT is true for TDX too, so it will also depend on
check order. It is fragile.

Frankly, naked sme_me_mask check would be better. Hm?

-- 
 Kirill A. Shutemov