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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id e1sm3109303pfi.175.2021.03.31.12.56.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Mar 2021 12:56:15 -0700 (PDT) From: Kees Cook To: Sean Christopherson , Michal Marek , Masahiro Yamada , Nathan Chancellor , Nick Desaulniers Cc: Kees Cook , Sami Tolvanen , clang-built-linux@googlegroups.com, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kbuild: Merge module sections if and only if CONFIG_LTO_CLANG is enabled Date: Wed, 31 Mar 2021 12:56:02 -0700 Message-Id: <161722055925.1870138.4983509937620008210.b4-ty@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210322234438.502582-1-seanjc@google.com> References: <20210322234438.502582-1-seanjc@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 22 Mar 2021 16:44:38 -0700, Sean Christopherson wrote: > Merge module sections only when using Clang LTO. With gcc-10, merging > sections does not appear to update the symbol tables for the module, > e.g. 'readelf -s' shows the value that a symbol would have had, if > sections were not merged. > > The stale symbol table breaks gdb's function disassambler, and presumably > other things, e.g. > > [...] Applied to for-linus/lto, thanks! [1/1] kbuild: lto: Merge module sections if and only if CONFIG_LTO_CLANG is enabled https://git.kernel.org/kees/c/8b382ebc86a8 -- Kees Cook