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Peter Anvin" , the arch/x86 maintainers , "Peter Zijlstra (Intel)" , Ard Biesheuvel , Nadav Amit , Masahiro Yamada , LKML Subject: Re: [PATCH v6 02/27] x86: Use symbol name in jump table for PIE support Message-ID: <20190207171145.GH2414@zn.tnic> References: <20190131192533.34130-1-thgarnie@chromium.org> <20190131192533.34130-3-thgarnie@chromium.org> <20190207121729.GE2414@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 07, 2019 at 09:04:45AM -0800, Thomas Garnier wrote: > I assume that's an optimisation done by gcc later. So why is that change even needed? Where does it break? > The P modifier in the documentation does state that it is used to > generate PIC code. The documentation says: "If used for a function, print the PLT suffix and generate PIC code. For example, emit foo@PLT instead of ’foo’ for the function foo()." when you use %P for a function. Which is not how it is used here. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.