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Peter Anvin" , Andy Lutomirski , Ard Biesheuvel , Josh Poimboeuf , Paolo Bonzini , "H.J. Lu" , clang-built-linux Message-ID: <482526608.2543.1588773672085.JavaMail.zimbra@efficios.com> In-Reply-To: <20200506135502.GS3762@hirez.programming.kicks-ass.net> References: <20200501202849.647891881@infradead.org> <656098739.766.1588705237442.JavaMail.zimbra@efficios.com> <470458191.1021.1588710464160.JavaMail.zimbra@efficios.com> <20200506135502.GS3762@hirez.programming.kicks-ass.net> Subject: Re: [PATCH v4 14/18] static_call: Add static_cond_call() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_3928 (ZimbraWebClient - FF76 (Linux)/8.8.15_GA_3928) Thread-Topic: static_call: Add static_cond_call() Thread-Index: /XazMzaob2R7RnrpgfiHRnqwczHCZA== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- On May 6, 2020, at 9:55 AM, Peter Zijlstra peterz@infradead.org wrote: > On Tue, May 05, 2020 at 04:27:44PM -0400, Mathieu Desnoyers wrote: >> Actually, if the goal is to do code patching of the call, I wonder >> what makes it OK to "guess" all the call patterns generated by the compiler ? > > We're not guessing, have have objtool read the compiler output and > record the location for us. The compiler can generate whatever it likes. So is the plan to adapt objtool if future compilers change the generated instruction patterns ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com