From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1FD09C43219 for ; Tue, 30 Apr 2019 17:11:25 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6051A20644 for ; Tue, 30 Apr 2019 17:11:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6051A20644 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44tp2y3C1mzDqSB for ; Wed, 1 May 2019 03:11:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=arm.com (client-ip=217.140.101.70; helo=foss.arm.com; envelope-from=sudeep.holla@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by lists.ozlabs.org (Postfix) with ESMTP id 44tp1L31jHzDqNy for ; Wed, 1 May 2019 03:09:56 +1000 (AEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8B845374; Tue, 30 Apr 2019 10:09:55 -0700 (PDT) Received: from [10.1.196.42] (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 66A103F5C1; Tue, 30 Apr 2019 10:09:52 -0700 (PDT) Subject: Re: [PATCH v2 3/6] x86: clean up _TIF_SYSCALL_EMU handling using ptrace_syscall_enter hook To: Andy Lutomirski References: <20190318104925.16600-1-sudeep.holla@arm.com> <20190318104925.16600-4-sudeep.holla@arm.com> From: Sudeep Holla Organization: ARM Message-ID: Date: Tue, 30 Apr 2019 18:09:50 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Haibo Xu , Steve Capper , Catalin Marinas , Jeff Dike , X86 ML , Will Deacon , LKML , Oleg Nesterov , Richard Weinberger , Ingo Molnar , Paul Mackerras , Sudeep Holla , Borislav Petkov , Thomas Gleixner , Bin Lu , linuxppc-dev , linux-arm-kernel Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 30/04/2019 17:46, Andy Lutomirski wrote: > On Mon, Mar 18, 2019 at 3:49 AM Sudeep Holla wrote: >> >> Now that we have a new hook ptrace_syscall_enter that can be called from >> syscall entry code and it handles PTRACE_SYSEMU in generic code, we >> can do some cleanup using the same in syscall_trace_enter. >> >> Further the extra logic to find single stepping PTRACE_SYSEMU_SINGLESTEP >> in syscall_slow_exit_work seems unnecessary. Let's remove the same. >> > > Unless the patch set contains a selftest that exercises all the > interesting cases here, NAK. To be clear, there needs to be a test > that passes on an unmodified kernel and still passes on a patched > kernel. And that test case needs to *fail* if, for example, you force > "emulated" to either true or false rather than reading out the actual > value. > Tested using tools/testing/selftests/x86/ptrace_syscall.c Also v3 doesn't change any logic or additional call to new function as in v2. It's just simple cleanup as suggested by Oleg. -- Regards, Sudeep