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References: <20220622162230.83474-1-kirill.shutemov@linux.intel.com> <20220622162230.83474-9-kirill.shutemov@linux.intel.com>
In-Reply-To: <20220622162230.83474-9-kirill.shutemov@linux.intel.com>
From:   Alexander Potapenko <glider@google.com>
Date:   Thu, 30 Jun 2022 12:06:47 +0200
Message-ID: <CAG_fn=VFOFjYmT5o3jLe+qKo4A1qp8N0=USeyzbb-hcdYChK6Q@mail.gmail.com>
Subject: Re: [PATCHv4 OPTIONAL 8/8] x86/mm: Extend LAM to support to LAM_U48
To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc:     Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        Kostya Serebryany <kcc@google.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Andrey Konovalov <andreyknvl@gmail.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>,
        Linux Memory Management List <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Wed, Jun 22, 2022 at 6:23 PM Kirill A. Shutemov
<kirill.shutemov@linux.intel.com> wrote:
>
> LAM_U48 allows to encode 15 bits of tags into address.
>
> LAM_U48 steals bits above 47-bit for tags and makes it impossible for
> userspace to use full address space on 5-level paging machine.
>
> Make these features mutually exclusive: whichever gets enabled first
> blocks the other one.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>


> @@ -206,11 +209,15 @@ const char *arch_vma_name(struct vm_area_struct *vm=
a)
>   * the failure of such a fixed mapping request, so the restriction is no=
t
>   * applied.
>   */
> -bool mmap_address_hint_valid(unsigned long addr, unsigned long len)
> +bool mmap_address_hint_valid(struct mm_struct *mm,
> +                            unsigned long addr, unsigned long len)
Please make sure to reflect the newly added parameter in the doc comment.
This may also apply to other patches in the series.


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