Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752392AbaKLLHL (ORCPT ); Wed, 12 Nov 2014 06:07:11 -0500 Received: from mail-pa0-f46.google.com ([209.85.220.46]:41044 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751359AbaKLLHJ (ORCPT ); Wed, 12 Nov 2014 06:07:09 -0500 Message-ID: <54633F53.8020507@linaro.org> Date: Wed, 12 Nov 2014 20:06:59 +0900 From: AKASHI Takahiro User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Will Deacon CC: Oleg Nesterov , "roland@hack.frob.com" , "linux@arm.linux.org.uk" , "dsaxena@linaro.org" , "keescook@chromium.org" , "linux-arm-kernel@lists.infradead.org" , "linaro-kernel@lists.linaro.org" , "linux-kernel@vger.kernel.org" Subject: Re: [RFC] ptrace: add generic SET_SYSCALL request References: <1415346443-28915-1-git-send-email-takahiro.akashi@linaro.org> <20141107140405.GA30156@redhat.com> <54633A69.6090202@linaro.org> <20141112110047.GB26437@arm.com> In-Reply-To: <20141112110047.GB26437@arm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/12/2014 08:00 PM, Will Deacon wrote: > On Wed, Nov 12, 2014 at 10:46:01AM +0000, AKASHI Takahiro wrote: >> On 11/07/2014 11:04 PM, Oleg Nesterov wrote: >>> To me the fact that PTRACE_SET_SYSCALL can be undefined and syscall_set_nr() >>> is very much arch-dependant (but most probably trivial) means that this code >>> should live in arch_ptrace(). >> >> Thinking of Oleg's comment above, it doesn't make sense neither to define generic >> NT_SYSTEM_CALL (user_regset) in uapi/linux/elf.h and implement it in ptrace_regset() >> in kernel/ptrace.c with arch-defined syscall_(g)set_nr(). >> >> Since we should have the same interface on arm and arm64, we'd better implement >> ptrace(PTRACE_SET_SYSCALL) locally on arm64 for now (as I originally submitted). > > I think the regset approach is cleaner. We already do something similar for > TLS. That would be implemented under arch/arm64/ with it's own NT type. Okey, so arm64 goes its own way :) Or do you want to have a similar regset on arm, too? (In this case, NT_ARM_SYSTEM_CALL can be shared in uapi/linux/elf.h) -Takahiro AKASHI > 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/