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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id h16sm4507596pfo.185.2020.11.20.11.47.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 11:47:22 -0800 (PST) Date: Fri, 20 Nov 2020 11:47:21 -0800 From: Kees Cook To: Sami Tolvanen Cc: Nick Desaulniers , Masahiro Yamada , Steven Rostedt , Will Deacon , Josh Poimboeuf , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , linux-pci@vger.kernel.org Subject: Re: [PATCH v7 02/17] kbuild: add support for Clang LTO Message-ID: <202011201144.3F2BB70C@keescook> References: <20201118220731.925424-1-samitolvanen@google.com> <20201118220731.925424-3-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 20, 2020 at 08:23:11AM -0800, Sami Tolvanen wrote: > Changing the ThinLTO config to a choice and moving it after the main > LTO config sounds like a good idea to me. I'll see if I can change > this in v8. Thanks! Originally, I thought this might be a bit ugly once GCC LTO is added, but this could be just a choice like we're done for the stack initialization. Something like an "LTO" choice of NONE, CLANG_FULL, CLANG_THIN, and in the future GCC, etc. -- Kees Cook