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Lu" Cc: "Kirill A. Shutemov" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , "the arch/x86 maintainers" , Andrey Ryabinin , Alexander Potapenko , Catalin Marinas , Will Deacon , Andi Kleen , Linux-MM , LKML , GNU C Library , GCC Development Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 5, 2021 at 4:43 PM H.J. Lu wrote: > > On Fri, Feb 5, 2021 at 7:16 AM Kirill A. Shutemov > 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 Hi Kirill, H.J., I don't have strong preference for PR_SET/GET_TAGGED_ADDR_CTRL vs ARCH_X86_FEATURE_1_ENABLE itself, but tying LAM to ELF and GNU_PROPERTY in the second option looks strange. LAM can be used outside of ELF/GNU, right?