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Date:   Wed, 19 Oct 2022 03:17:28 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     "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>, 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
Subject: Re: [PATCHv10 10/15] x86/mm, iommu/sva: Make LAM and SVM mutually
 exclusive
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On Tue, Oct 18, 2022 at 03:43:24PM -0700, Dave Hansen wrote:
> On 10/18/22 15:33, Kirill A. Shutemov wrote:
> >> Is this #ifdef really necessary?  CONFIG_IOMMU_SVA selects IOASID,
> >> without which pasid_valid() is just stubbed out to 0.
> > mm->pasid is only defined for CONFIG_IOMMU_SVA=y.
> > 
> > Do you want me to add mm_has_valid_pasid()?
> 
> A quick grep makes it look like pasid_valid() could be *replaced* with
> mm_has_pasid_valid() since all the places doing pasid_valid() do it with
> mm->pasid.

Almost: the second pasid_valid() in iommu_sva_alloc_pasid() called for
just allocated pasid.

I guess we can just opencode this case.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov