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Date:   Wed, 19 Oct 2022 12:34:15 +0530
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Subject: Re: [PATCHv10 10/15] x86/mm, iommu/sva: Make LAM and SVM mutually
 exclusive
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     x86@kernel.org, Kostya Serebryany <kcc@google.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Alexander Potapenko <glider@google.com>,
        Taras Madan <tarasmadan@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "H . J . Lu" <hjl.tools@gmail.com>,
        Andi Kleen <ak@linux.intel.com>,
        Rick Edgecombe <rick.p.edgecombe@intel.com>,
        Bharata B Rao <bharata@amd.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Ashok Raj <ashok.raj@intel.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20221018113358.7833-1-kirill.shutemov@linux.intel.com>
 <20221018113358.7833-11-kirill.shutemov@linux.intel.com>
From:   Vasant Hegde <vasant.hegde@amd.com>
In-Reply-To: <20221018113358.7833-11-kirill.shutemov@linux.intel.com>
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Hi Kirill,

On 10/18/2022 5:03 PM, Kirill A. Shutemov wrote:
> IOMMU and SVM-capable devices know nothing about LAM and only expect
> canonical addresses. Attempt to pass down tagged pointer will lead to
> address translation failure.
> 
> By default do not allow to enable both LAM and use SVM in the same
> process.
> 
> The new ARCH_FORCE_TAGGED_SVM arch_prctl() overrides the limitation.

Better s/SVM/SVA/ ? So that its consistent with IOMMU usage.

-Vasant