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References: <20210205151631.43511-1-kirill.shutemov@linux.intel.com> <20210205151631.43511-11-kirill.shutemov@linux.intel.com>
In-Reply-To: <20210205151631.43511-11-kirill.shutemov@linux.intel.com>
From:   "H.J. Lu" <hjl.tools@gmail.com>
Date:   Fri, 5 Feb 2021 07:42:36 -0800
Message-ID: <CAMe9rOrhPNs7WZa7DquEQf_YN4XyeDZC5u3XC7MBDija3ic3+Q@mail.gmail.com>
Subject: Re: [RFC 9/9] x86/mm: Implement PR_SET/GET_TAGGED_ADDR_CTRL with LAM
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>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, Andi Kleen <ak@linux.intel.com>,
        Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        GNU C Library <libc-alpha@sourceware.org>,
        GCC Development <gcc@gcc.gnu.org>
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On Fri, Feb 5, 2021 at 7:16 AM Kirill A. Shutemov
<kirill.shutemov@linux.intel.com> wrote:
>
> Provide prctl() interface to enabled LAM for user addresses. Depending
> how many tag bits requested it may result in enabling LAM_U57 or
> LAM_U48.

I prefer the alternate kernel interface based on CET arch_prctl interface which
is implemented in glibc on users/intel/lam/master branch:

https://gitlab.com/x86-glibc/glibc/-/tree/users/intel/lam/master

and in GCC on users/intel/lam/master branch:

https://gitlab.com/x86-gcc/gcc/-/tree/users/intel/lam/master

-- 
H.J.