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Lu" , "H. Peter Anvin" , jannh@google.com, Kees Cook , linux-api@vger.kernel.org, linux-arch , Linux Doc Mailing List , LKML , linux-mm@kvack.org, luto@kernel.org, mike.kravetz@oracle.com, Ingo Molnar , nadav.amit@gmail.com, oleg@redhat.com, pavel@ucw.cz, pengfei.xu@intel.com, Peter Zijlstra , ravi.v.shankar@intel.com, Randy Dunlap , Thomas Gleixner , vedvyas.shanbhogue@intel.com, weijiang.yang@intel.com, X86 ML , Luis Lozano , clang-built-linux , erich.keane@intel.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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 Mon, Nov 30, 2020 at 10:34 AM Yu, Yu-cheng wrote= : > > On 11/30/2020 10:26 AM, Nick Desaulniers wrote: > > (In response to https://lore.kernel.org/lkml/20201110162211.9207-2-yu-c= heng.yu@intel.com/) > > > >> These need to be enabled to build a CET-enabled kernel, and Binutils v= 2.31 > >> and GCC v8.1 or later are required to build a CET kernel. > > > > What about LLVM? Surely CrOS might be of interest to ship this on (we s= hip the > > equivalent for aarch64 on Android). > > > > I have not built with LLVM, but think it probably will work as well. I > will test it. > > >> An application's CET capability is marked in its ELF header and can be > >> verified from the following command output, in the NT_GNU_PROPERTY_TYP= E_0 > >> field: > >> > >> readelf -n | grep SHSTK > >> properties: x86 feature: IBT, SHSTK > > > > Same for llvm-readelf. > > > > I will add that to the document. > > Thanks, > Yu-cheng The baseline LLVM version is 10.0.1, which is good enough for clang -fcf-protection=3Dfull, llvm-readelf -n, LLD's .note.gnu.property handling (the LLD option is `-z force-ibt`, though) --=20 =E5=AE=8B=E6=96=B9=E7=9D=BF