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=-1.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 10190C43219 for ; Tue, 30 Apr 2019 16:47:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D44D621734 for ; Tue, 30 Apr 2019 16:47:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556642830; bh=S48pNAsTw7BEZ36AW1e1TSyWImwtIKer4k1K+rKGgdc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=shtrajp3A8HQM4KLoZna6Hcjc5JwU6DDf81i6q0CtTz9cmYfbhKjX4F722NEiFwre 3Wriq0IzVL6wmLs37aXJC5c0Qn6uQBj5nej0TqZHfImxsnqvQC7IMU1ZrDjC1QJD8W yk+PGEE7tp9Wu+H7rt46HxYPSnC293Jq3SCGmS1Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726401AbfD3QrJ (ORCPT ); Tue, 30 Apr 2019 12:47:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:36024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726017AbfD3QrJ (ORCPT ); Tue, 30 Apr 2019 12:47:09 -0400 Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 26F482173E for ; Tue, 30 Apr 2019 16:47:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556642828; bh=S48pNAsTw7BEZ36AW1e1TSyWImwtIKer4k1K+rKGgdc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=OfHCGrtUbiFJqLJB8TSFf7ldICXZA8iqik5XHx+uu4ZsE2UzlSk2VQWW6WYUsnUZr hB6najoPJUOCFObaMzBNFOEjtzUHebohanEO9HfhAwUAKuM2Lq8Up3CVLv213XzgBu yfoLpbcuVy3Wm2yY972dudRHvVjBb4hHzg0rXing= Received: by mail-wr1-f50.google.com with SMTP id k16so21839887wrn.5 for ; Tue, 30 Apr 2019 09:47:08 -0700 (PDT) X-Gm-Message-State: APjAAAWh+HnjCq9W83ZwzmompChx+3SKqFSGf8JEYPBxmRWvkNhIH7pY 86tSjtKwrZjo3bP92reWK39wf4sAT2SXEbCvKNHRAA== X-Google-Smtp-Source: APXvYqzHEqvh6x3xmyRtRqKnO98xcUmDJgjMNHD1klJcb2L6wbWRNt5Tm23i28W+RKElRE+GeRwRbM4AmqFkXIl8JL4= X-Received: by 2002:a5d:4e82:: with SMTP id e2mr2206324wru.199.1556642826765; Tue, 30 Apr 2019 09:47:06 -0700 (PDT) MIME-Version: 1.0 References: <20190318104925.16600-1-sudeep.holla@arm.com> <20190318104925.16600-4-sudeep.holla@arm.com> In-Reply-To: <20190318104925.16600-4-sudeep.holla@arm.com> From: Andy Lutomirski Date: Tue, 30 Apr 2019 09:46:54 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 3/6] x86: clean up _TIF_SYSCALL_EMU handling using ptrace_syscall_enter hook To: Sudeep Holla Cc: X86 ML , linux-arm-kernel , LKML , linuxppc-dev , Catalin Marinas , Will Deacon , Oleg Nesterov , Paul Mackerras , Michael Ellerman , Thomas Gleixner , Ingo Molnar , Richard Weinberger , Jeff Dike , Steve Capper , Haibo Xu , Bin Lu , Andy Lutomirski , Borislav Petkov Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. --Andy 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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 0B0A3C43219 for ; Tue, 30 Apr 2019 16:52:04 +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 3D5252147A for ; Tue, 30 Apr 2019 16:52:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="OfHCGrtU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3D5252147A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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 44tncd2l27zDqXX for ; Wed, 1 May 2019 02:52:01 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=luto@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="OfHCGrtU"; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44tnW26WBjzDqRK for ; Wed, 1 May 2019 02:47:10 +1000 (AEST) Received: from mail-wr1-f46.google.com (mail-wr1-f46.google.com [209.85.221.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1DAC82147A for ; Tue, 30 Apr 2019 16:47:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556642828; bh=S48pNAsTw7BEZ36AW1e1TSyWImwtIKer4k1K+rKGgdc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=OfHCGrtUbiFJqLJB8TSFf7ldICXZA8iqik5XHx+uu4ZsE2UzlSk2VQWW6WYUsnUZr hB6najoPJUOCFObaMzBNFOEjtzUHebohanEO9HfhAwUAKuM2Lq8Up3CVLv213XzgBu yfoLpbcuVy3Wm2yY972dudRHvVjBb4hHzg0rXing= Received: by mail-wr1-f46.google.com with SMTP id a9so21825896wrp.6 for ; Tue, 30 Apr 2019 09:47:08 -0700 (PDT) X-Gm-Message-State: APjAAAUG7Y5FLtTwPo0XLWFis3of2ThWibyvio3G286GtyB7tFfZ7a9K No9iGr/6vdcT71zoJxP7eCBO5bREisRledtI1Ei6cw== X-Google-Smtp-Source: APXvYqzHEqvh6x3xmyRtRqKnO98xcUmDJgjMNHD1klJcb2L6wbWRNt5Tm23i28W+RKElRE+GeRwRbM4AmqFkXIl8JL4= X-Received: by 2002:a5d:4e82:: with SMTP id e2mr2206324wru.199.1556642826765; Tue, 30 Apr 2019 09:47:06 -0700 (PDT) MIME-Version: 1.0 References: <20190318104925.16600-1-sudeep.holla@arm.com> <20190318104925.16600-4-sudeep.holla@arm.com> In-Reply-To: <20190318104925.16600-4-sudeep.holla@arm.com> From: Andy Lutomirski Date: Tue, 30 Apr 2019 09:46:54 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 3/6] x86: clean up _TIF_SYSCALL_EMU handling using ptrace_syscall_enter hook To: Sudeep Holla Content-Type: text/plain; charset="UTF-8" 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 , Andy Lutomirski , 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 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. --Andy 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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 E0080C43219 for ; Tue, 30 Apr 2019 16:47:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 AFD762147A for ; Tue, 30 Apr 2019 16:47:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CNtK7oko"; 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Tue, 30 Apr 2019 09:47:08 -0700 (PDT) X-Gm-Message-State: APjAAAU0i+4ou6sCOPGtalMYu7ASIizXFveXaZHoG0IwljiOOkiVXGov XoXylQGSiLtczBKbNkychu1k2nsU3UNq0KDvHmPoFg== X-Google-Smtp-Source: APXvYqzHEqvh6x3xmyRtRqKnO98xcUmDJgjMNHD1klJcb2L6wbWRNt5Tm23i28W+RKElRE+GeRwRbM4AmqFkXIl8JL4= X-Received: by 2002:a5d:4e82:: with SMTP id e2mr2206324wru.199.1556642826765; Tue, 30 Apr 2019 09:47:06 -0700 (PDT) MIME-Version: 1.0 References: <20190318104925.16600-1-sudeep.holla@arm.com> <20190318104925.16600-4-sudeep.holla@arm.com> In-Reply-To: <20190318104925.16600-4-sudeep.holla@arm.com> From: Andy Lutomirski Date: Tue, 30 Apr 2019 09:46:54 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 3/6] x86: clean up _TIF_SYSCALL_EMU handling using ptrace_syscall_enter hook To: Sudeep Holla X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190430_094709_470260_293FA01F X-CRM114-Status: GOOD ( 14.31 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: 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 , Andy Lutomirski , Michael Ellerman , Borislav Petkov , Thomas Gleixner , Bin Lu , linuxppc-dev , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. --Andy _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel