Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752256AbaKZKJV (ORCPT ); Wed, 26 Nov 2014 05:09:21 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:39496 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751261AbaKZKJT (ORCPT ); Wed, 26 Nov 2014 05:09:19 -0500 Date: Wed, 26 Nov 2014 10:09:19 +0000 From: Will Deacon To: David Long Cc: Sandeepa Prabhu , "linux-arm-kernel@lists.infradead.org" , Russell King , William Cohen , Catalin Marinas , "Jon Medhurst (Tixy)" , Masami Hiramatsu , Ananth N Mavinakayanahalli , Anil S Keshavamurthy , "davem@davemloft.net" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 1/5] arm64: Kprobes with single stepping support Message-ID: <20141126100919.GA9040@arm.com> References: <1416292375-29560-1-git-send-email-dave.long@linaro.org> <1416292375-29560-2-git-send-email-dave.long@linaro.org> <20141118145643.GO18842@arm.com> <20141119112553.GC15985@arm.com> <546CAF5A.4060901@linaro.org> <54757734.4060301@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54757734.4060301@linaro.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 26, 2014 at 06:46:12AM +0000, David Long wrote: > On 11/19/14 09:55, David Long wrote: > > On 11/19/14 06:25, Will Deacon wrote: > >> I was thinking of the magic hex numbers in the kprobes decode tables, > >> which > >> seem to correspond directly to the instruction classes described in > >> insn.c > >> > >> Keeping the actual emulation code separate makes sense. > >> > > Of course that follows the model of the much more complex arm32 > > kprobes/uprobes decoding. I can have a go at replacing it with insn.c > > calls. > > While the existing aarch64_get_insn_class() function in insn.c is > somewhat useful here what is really needed is a function that identifies > if an instruction uses the pc (branch, load literal, load address). > Such instructions cannot be arbitrarily moved around in isolation, and > do not fall neatly into the existing "class"es. I've written a simple > aarch64_insn_uses_pc() function to add to insn.c but I'd like to hear > agreement that this is a good approach before sending out the patch. > Thoughts? I'm perfectly happy with extending insn.c with extra helpers if they're useful to you. Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/