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=-2.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 0FE64C43387 for ; Fri, 14 Dec 2018 19:29:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AD7F206E0 for ; Fri, 14 Dec 2018 19:29:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=armh.onmicrosoft.com header.i=@armh.onmicrosoft.com header.b="FBnn188s" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730647AbeLNT3o (ORCPT ); Fri, 14 Dec 2018 14:29:44 -0500 Received: from mail-eopbgr20051.outbound.protection.outlook.com ([40.107.2.51]:63940 "EHLO EUR02-VE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730123AbeLNT3o (ORCPT ); Fri, 14 Dec 2018 14:29:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector1-arm-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=1VR2BRpsO929GsbFygTnAfa0/M/uLjo4tGJWuJuINUA=; b=FBnn188soZGTH3k0SdlBTnJqsDbcYWFRoAzRD4/HzXoHtMAp2R3cvNg7Gfc7iT8Wty39LgcK7uQknanSBUDBVtYCkc211LB+VoyqtDl4+lGLxKcJ3q7DFRxprGp79Zm8OnEy+Fj0zh+Z0pcPgkhtSTMNBM89FxB2XWN68rjuY0A= Received: from DB8PR08MB4107.eurprd08.prod.outlook.com (20.179.11.13) by DB8PR08MB4042.eurprd08.prod.outlook.com (20.179.10.28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1425.22; Fri, 14 Dec 2018 19:28:57 +0000 Received: from DB8PR08MB4107.eurprd08.prod.outlook.com ([fe80::3c72:426b:5847:22e3]) by DB8PR08MB4107.eurprd08.prod.outlook.com ([fe80::3c72:426b:5847:22e3%5]) with mapi id 15.20.1404.026; Fri, 14 Dec 2018 19:28:57 +0000 From: Dave P Martin To: Szabolcs Nagy CC: nd , "linux-arm-kernel@lists.infradead.org" , Will Deacon , "linux-kernel@vger.kernel.org" , Alan Hayward Subject: Re: [PATCH 0/3] arm64/sve: UAPI: Disentangle ptrace.h from sigcontext.h Thread-Topic: [PATCH 0/3] arm64/sve: UAPI: Disentangle ptrace.h from sigcontext.h Thread-Index: AQHUkYd5TQtknm9R4kqjkh+b7I8GJaV+jmIAgAADSQCAAAm4gIAACA+A Date: Fri, 14 Dec 2018 19:28:57 +0000 Message-ID: <20181214192855.GD4719@e103592.cambridge.arm.com> References: <1544556407-19897-1-git-send-email-Dave.Martin@arm.com> <2abbbd29-cc87-a0ad-80b7-e2a1d039235e@arm.com> <20181214182518.GH3505@e103592.cambridge.arm.com> <5e96f169-d77d-63d0-11ba-f59f572b0219@arm.com> In-Reply-To: <5e96f169-d77d-63d0-11ba-f59f572b0219@arm.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mutt/1.5.23 (2014-03-12) x-originating-ip: [217.140.106.49] x-clientproxiedby: LO2P265CA0263.GBRP265.PROD.OUTLOOK.COM (2603:10a6:600:8a::35) To DB8PR08MB4107.eurprd08.prod.outlook.com (2603:10a6:10:ac::13) authentication-results: spf=none (sender IP is ) smtp.mailfrom=Dave.Martin@arm.com; x-ms-exchange-messagesentrepresentingtype: 1 x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;DB8PR08MB4042;6:/AbJXshxndZPkBb29Q1G/DKmU3q/dsOMjQfyZzdFsiEwB0sVFi4lFTBfq9Zh1NNnexVIFnHKLIrdOB/nTWeEhshl99zMOorMBCDH/0udCcNiro7Agn6DJ6wquzSD2OJpMjbSSON9W54r5DgtmvE2pdt471YL/CNqjvogmAgHFOQQ0QN+tjU3XcPLEP2JzbtVW4CGP9Y1Joi31U8cL9GBamVtxxmWrvYaBk/V0Uf+95V2EAQAkOa9bnieRhby0WR6KYxFGm7DSQeQXGnH0QXiNUCiogSTY8R0eM0J53tJcvfBY0Q5SLC6ZU+k7OKUOtltHGa5/UzAyVy5yzmvt/Ahs/EbReGLehBNq1jeiITG5cc0oKxOmdpX9gXB/+6wzBTaZySodVkkmDNp/TBVWTNZQCPQXZBx5/tRBx23A8rbV0534P4SaV5FnNI784jyqwpMPD2MyLU9tRS0Ieq+VWriZw==;5:d4lNf6FDZr/hdN4/wIKlbZx80zBqlm10WEI1aHSmKNNd2FNuyCiiqpTYkKkGu8owcLh6qlXi+xCRUcJ+RkyO9eLpEcC1GFrhs865Hw7KLpc3K7iaRnFSZgnopvFB+Df/ouRX+Vel92woEZSUXsaGZ8daLKAGHepED5XBntIrW+s=;7:ENuLTf4lsFqUNb+vUunQpwwB12GUZvIpIIDxEp2EzPfsq7stQLVqOmMoqyf18smLNIDtsT7hA2xJZ58OmEdfM3usjBGJ5gJa2FlR+O8CaWlvI94Wbrrj10Q5BXjs/6N/d8hS0ws7Gm2l/uMLUVo9NA== x-ms-office365-filtering-correlation-id: 30e1f369-5ef1-4a3f-1595-08d661fa6454 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600074)(711020)(4618075)(2017052603328)(7153060)(7193020);SRVR:DB8PR08MB4042; x-ms-traffictypediagnostic: DB8PR08MB4042: nodisclaimer: True x-microsoft-antispam-prvs: x-ms-exchange-senderadcheck: 1 x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(3230021)(999002)(6040522)(2401047)(8121501046)(5005006)(93006095)(93001095)(3231475)(944501520)(4982022)(52105112)(3002001)(10201501046)(6055026)(148016)(149066)(150057)(6041310)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123558120)(20161123560045)(20161123562045)(20161123564045)(201708071742011)(7699051)(76991095);SRVR:DB8PR08MB4042;BCL:0;PCL:0;RULEID:;SRVR:DB8PR08MB4042; x-forefront-prvs: 08864C38AC x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(366004)(39860400002)(346002)(376002)(136003)(396003)(199004)(189003)(6636002)(476003)(446003)(11346002)(2906002)(486006)(305945005)(97736004)(26005)(71190400001)(186003)(71200400001)(256004)(6486002)(76176011)(53546011)(386003)(102836004)(5660300001)(6436002)(229853002)(3846002)(86362001)(6116002)(1076002)(478600001)(53936002)(14454004)(7736002)(72206003)(966005)(54906003)(6506007)(66066001)(4326008)(99286004)(6862004)(52116002)(93886005)(33656002)(6512007)(316002)(58126008)(6306002)(106356001)(68736007)(6246003)(25786009)(105586002)(81156014)(8936002)(8676002)(81166006)(18370500001);DIR:OUT;SFP:1101;SCL:1;SRVR:DB8PR08MB4042;H:DB8PR08MB4107.eurprd08.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: arm.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: d34bPWIS+mheXW2l6JCjLn9+rblso/T/dVNjjpSNp8ztQr9Pc0iFP67JBuJqGvqTmYy8bMjKmLh13CubY0xBGXB9QKsJM5PdqOLPVxT5PBnNv5fupagMzUCBi2BjTBHbh7/s/049dwROmIiO6O0b/glQYp21C2CxtJWaJu5kXOXY41VTXO/xegPg8svAoNQtks3+wJivuhiC+Ct2ANF7DYzbZjEUPBqlXd4+MbnFrS6BJRHhhZIOQK7pQlfdyUDeYKBhYnAhQQe2neD/6ZGvNNg+W6kAPis0wzK5NQsVV30TFdWat5hLAq5PN2/Wm7RA spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-Network-Message-Id: 30e1f369-5ef1-4a3f-1595-08d661fa6454 X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Dec 2018 19:28:57.4775 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB8PR08MB4042 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 14, 2018 at 07:00:07PM +0000, Szabolcs Nagy wrote: > On 14/12/2018 18:25, Dave Martin wrote: > > On Fri, Dec 14, 2018 at 06:13:33PM +0000, Szabolcs Nagy wrote: > >> On 11/12/2018 19:26, Dave Martin wrote: > >>> This patch refactors the UAPI header definitions for the Arm SVE > >>> extension to avoid multiple-definition problems when userspace mixes = its > >>> own sigcontext.h definitions with the kernel's ptrace.h (which is > >>> apparently routine). > >>> > >>> A common backend header is created to hold common definitions, suitab= ly > >>> namespaced, and with an appropriate header guard. > >>> > >>> See the commit message in patch 3 for further explanation of why this > >>> is needed. > >>> > >>> Because of the non-trivial header guard in the new sve_context.h, pat= ch > >>> 1 adds support to headers_install.sh to munge #if defined(_UAPI_FOO) = in > >>> a similar way to the current handling of #ifndef _UAPI_FOO. > >>> > >> > >> thanks for doing this. > >> > >> the patches fix the gdb build issue on musl libc with an > >> additional gdb patch: > >> https://sourceware.org/ml/gdb-patches/2018-12/msg00152.html > >> (in userspace i'd expect users relying on signal.h providing > >> whatever is in asm/sigcontext.h.) > >> > >> i think sve_context.h could be made to work with direct include, > >> even if that's not useful because there is no public api there. > >> (and then you dont need the first patch) > >=20 > > My general view is that if you want the sigframe types userspace should > > usually include and refer to mcontext_t. > >=20 >=20 > ucontext.h does not expose the asm/sigcontext.h types in glibc, > but it is compatible with the inclusion of asm/sigcontext.h > (or signal.h). >=20 > in musl ucontext.h includes signal.h and signal.h provides > the asm/sigcontext.h api with abi compatible definitions. >=20 > > Because the prototype for sa_sigaction() specifies a void * for the > > ucontext argument, I've generally assumed that is not > > sufficient to get ucontext_t (or mcontext_t) (but maybe I'm too paranoi= d > > there). >=20 > http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/signal.h.html >=20 > "The header shall define the ucontext_t type as a structure > that shall include at least the following members: > ... > mcontext_t uc_mcontext A machine-specific representation of the saved > context." >=20 > so signal.h must define ucontext_t but mcontext_t can be opaque. > (it is opaque with posix conform feature tests to avoid > namespace pollution, but with _GNU_SOURCE defined all > asm/sigcontext.h apis are there and mcontext_t matches > struct sigcontext) I see. Sounds reasonable. > >=20 > > Non-POSIX-flavoured software might include directly. > > In glibc/musl libc will that conflict with , or can the two > > coexist? >=20 > if you compile e.g in standard conform mode then > i think signal.h and asm/sigcontext.h are compatible. So long as we don't break any existing usage (?) I guess this is fine. Cheers ---Dave 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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 6C0CCC43387 for ; Fri, 14 Dec 2018 19:29:18 +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 B9A09206E0 for ; Fri, 14 Dec 2018 19:29:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="SRnSN+6o"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=armh.onmicrosoft.com header.i=@armh.onmicrosoft.com header.b="FBnn188s" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B9A09206E0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-ID:In-Reply-To: References:Message-ID:Date:Subject:To:From:Reply-To:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XBgai2NSbZEUoq6FV30j5JwlsavKJhEbjonjAi1WDE8=; b=SRnSN+6omTqPYR anpey3sVPwk1JVRidLXCjc9UWmv3t1ACcog4kVFz7erQUW0cQlRAc1JW8DrLJIVYnrGlNGiVy9FfN ZgARLSgvNktKlPaCISjMMo4o+ynoaIKxWq/KnKu0DabmEfZpx4jbDKIbKrIDyam6rU5EHevb1bYmm VbsqGJYy2Wf29vXZAhTL2Bzc3vVkUgIdsFRqFE3uhJ6vPtFFFbUwm5LKyaDi1fUVkGOrxhyTEaxie Zi3kBIAlFsnpwqNmFudt2KwpzO43iOkkqB5ZfwyoCOn0eJkSNzz36Wfc8m+BDKT5HP6Jw3VYbbc4G tR3qi4eR3hwkjENhAFTQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXt9A-0001MW-I1; Fri, 14 Dec 2018 19:29:16 +0000 Received: from mail-am5eur03on0602.outbound.protection.outlook.com ([2a01:111:f400:fe08::602] helo=EUR03-AM5-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXt96-0001Ls-Rw for linux-arm-kernel@lists.infradead.org; Fri, 14 Dec 2018 19:29:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector1-arm-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=1VR2BRpsO929GsbFygTnAfa0/M/uLjo4tGJWuJuINUA=; b=FBnn188soZGTH3k0SdlBTnJqsDbcYWFRoAzRD4/HzXoHtMAp2R3cvNg7Gfc7iT8Wty39LgcK7uQknanSBUDBVtYCkc211LB+VoyqtDl4+lGLxKcJ3q7DFRxprGp79Zm8OnEy+Fj0zh+Z0pcPgkhtSTMNBM89FxB2XWN68rjuY0A= Received: from DB8PR08MB4107.eurprd08.prod.outlook.com (20.179.11.13) by DB8PR08MB4042.eurprd08.prod.outlook.com (20.179.10.28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1425.22; Fri, 14 Dec 2018 19:28:57 +0000 Received: from DB8PR08MB4107.eurprd08.prod.outlook.com ([fe80::3c72:426b:5847:22e3]) by DB8PR08MB4107.eurprd08.prod.outlook.com ([fe80::3c72:426b:5847:22e3%5]) with mapi id 15.20.1404.026; Fri, 14 Dec 2018 19:28:57 +0000 From: Dave P Martin To: Szabolcs Nagy Subject: Re: [PATCH 0/3] arm64/sve: UAPI: Disentangle ptrace.h from sigcontext.h Thread-Topic: [PATCH 0/3] arm64/sve: UAPI: Disentangle ptrace.h from sigcontext.h Thread-Index: AQHUkYd5TQtknm9R4kqjkh+b7I8GJaV+jmIAgAADSQCAAAm4gIAACA+A Date: Fri, 14 Dec 2018 19:28:57 +0000 Message-ID: <20181214192855.GD4719@e103592.cambridge.arm.com> References: <1544556407-19897-1-git-send-email-Dave.Martin@arm.com> <2abbbd29-cc87-a0ad-80b7-e2a1d039235e@arm.com> <20181214182518.GH3505@e103592.cambridge.arm.com> <5e96f169-d77d-63d0-11ba-f59f572b0219@arm.com> In-Reply-To: <5e96f169-d77d-63d0-11ba-f59f572b0219@arm.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mutt/1.5.23 (2014-03-12) x-originating-ip: [217.140.106.49] x-clientproxiedby: LO2P265CA0263.GBRP265.PROD.OUTLOOK.COM (2603:10a6:600:8a::35) To DB8PR08MB4107.eurprd08.prod.outlook.com (2603:10a6:10:ac::13) authentication-results: spf=none (sender IP is ) smtp.mailfrom=Dave.Martin@arm.com; x-ms-exchange-messagesentrepresentingtype: 1 x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1; DB8PR08MB4042; 6:/AbJXshxndZPkBb29Q1G/DKmU3q/dsOMjQfyZzdFsiEwB0sVFi4lFTBfq9Zh1NNnexVIFnHKLIrdOB/nTWeEhshl99zMOorMBCDH/0udCcNiro7Agn6DJ6wquzSD2OJpMjbSSON9W54r5DgtmvE2pdt471YL/CNqjvogmAgHFOQQ0QN+tjU3XcPLEP2JzbtVW4CGP9Y1Joi31U8cL9GBamVtxxmWrvYaBk/V0Uf+95V2EAQAkOa9bnieRhby0WR6KYxFGm7DSQeQXGnH0QXiNUCiogSTY8R0eM0J53tJcvfBY0Q5SLC6ZU+k7OKUOtltHGa5/UzAyVy5yzmvt/Ahs/EbReGLehBNq1jeiITG5cc0oKxOmdpX9gXB/+6wzBTaZySodVkkmDNp/TBVWTNZQCPQXZBx5/tRBx23A8rbV0534P4SaV5FnNI784jyqwpMPD2MyLU9tRS0Ieq+VWriZw==; 5:d4lNf6FDZr/hdN4/wIKlbZx80zBqlm10WEI1aHSmKNNd2FNuyCiiqpTYkKkGu8owcLh6qlXi+xCRUcJ+RkyO9eLpEcC1GFrhs865Hw7KLpc3K7iaRnFSZgnopvFB+Df/ouRX+Vel92woEZSUXsaGZ8daLKAGHepED5XBntIrW+s=; 7:ENuLTf4lsFqUNb+vUunQpwwB12GUZvIpIIDxEp2EzPfsq7stQLVqOmMoqyf18smLNIDtsT7hA2xJZ58OmEdfM3usjBGJ5gJa2FlR+O8CaWlvI94Wbrrj10Q5BXjs/6N/d8hS0ws7Gm2l/uMLUVo9NA== x-ms-office365-filtering-correlation-id: 30e1f369-5ef1-4a3f-1595-08d661fa6454 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0; PCL:0; RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600074)(711020)(4618075)(2017052603328)(7153060)(7193020); SRVR:DB8PR08MB4042; x-ms-traffictypediagnostic: DB8PR08MB4042: nodisclaimer: True x-microsoft-antispam-prvs: x-ms-exchange-senderadcheck: 1 x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(8211001083)(3230021)(999002)(6040522)(2401047)(8121501046)(5005006)(93006095)(93001095)(3231475)(944501520)(4982022)(52105112)(3002001)(10201501046)(6055026)(148016)(149066)(150057)(6041310)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123558120)(20161123560045)(20161123562045)(20161123564045)(201708071742011)(7699051)(76991095); SRVR:DB8PR08MB4042; BCL:0; PCL:0; RULEID:; SRVR:DB8PR08MB4042; x-forefront-prvs: 08864C38AC x-forefront-antispam-report: SFV:NSPM; SFS:(10009020)(366004)(39860400002)(346002)(376002)(136003)(396003)(199004)(189003)(6636002)(476003)(446003)(11346002)(2906002)(486006)(305945005)(97736004)(26005)(71190400001)(186003)(71200400001)(256004)(6486002)(76176011)(53546011)(386003)(102836004)(5660300001)(6436002)(229853002)(3846002)(86362001)(6116002)(1076002)(478600001)(53936002)(14454004)(7736002)(72206003)(966005)(54906003)(6506007)(66066001)(4326008)(99286004)(6862004)(52116002)(93886005)(33656002)(6512007)(316002)(58126008)(6306002)(106356001)(68736007)(6246003)(25786009)(105586002)(81156014)(8936002)(8676002)(81166006)(18370500001); DIR:OUT; SFP:1101; SCL:1; SRVR:DB8PR08MB4042; H:DB8PR08MB4107.eurprd08.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1; received-spf: None (protection.outlook.com: arm.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: d34bPWIS+mheXW2l6JCjLn9+rblso/T/dVNjjpSNp8ztQr9Pc0iFP67JBuJqGvqTmYy8bMjKmLh13CubY0xBGXB9QKsJM5PdqOLPVxT5PBnNv5fupagMzUCBi2BjTBHbh7/s/049dwROmIiO6O0b/glQYp21C2CxtJWaJu5kXOXY41VTXO/xegPg8svAoNQtks3+wJivuhiC+Ct2ANF7DYzbZjEUPBqlXd4+MbnFrS6BJRHhhZIOQK7pQlfdyUDeYKBhYnAhQQe2neD/6ZGvNNg+W6kAPis0wzK5NQsVV30TFdWat5hLAq5PN2/Wm7RA spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-ID: MIME-Version: 1.0 X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-Network-Message-Id: 30e1f369-5ef1-4a3f-1595-08d661fa6454 X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Dec 2018 19:28:57.4775 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB8PR08MB4042 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181214_112912_951802_8E926E27 X-CRM114-Status: GOOD ( 22.82 ) 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: nd , Will Deacon , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Alan Hayward 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 Fri, Dec 14, 2018 at 07:00:07PM +0000, Szabolcs Nagy wrote: > On 14/12/2018 18:25, Dave Martin wrote: > > On Fri, Dec 14, 2018 at 06:13:33PM +0000, Szabolcs Nagy wrote: > >> On 11/12/2018 19:26, Dave Martin wrote: > >>> This patch refactors the UAPI header definitions for the Arm SVE > >>> extension to avoid multiple-definition problems when userspace mixes its > >>> own sigcontext.h definitions with the kernel's ptrace.h (which is > >>> apparently routine). > >>> > >>> A common backend header is created to hold common definitions, suitably > >>> namespaced, and with an appropriate header guard. > >>> > >>> See the commit message in patch 3 for further explanation of why this > >>> is needed. > >>> > >>> Because of the non-trivial header guard in the new sve_context.h, patch > >>> 1 adds support to headers_install.sh to munge #if defined(_UAPI_FOO) in > >>> a similar way to the current handling of #ifndef _UAPI_FOO. > >>> > >> > >> thanks for doing this. > >> > >> the patches fix the gdb build issue on musl libc with an > >> additional gdb patch: > >> https://sourceware.org/ml/gdb-patches/2018-12/msg00152.html > >> (in userspace i'd expect users relying on signal.h providing > >> whatever is in asm/sigcontext.h.) > >> > >> i think sve_context.h could be made to work with direct include, > >> even if that's not useful because there is no public api there. > >> (and then you dont need the first patch) > > > > My general view is that if you want the sigframe types userspace should > > usually include and refer to mcontext_t. > > > > ucontext.h does not expose the asm/sigcontext.h types in glibc, > but it is compatible with the inclusion of asm/sigcontext.h > (or signal.h). > > in musl ucontext.h includes signal.h and signal.h provides > the asm/sigcontext.h api with abi compatible definitions. > > > Because the prototype for sa_sigaction() specifies a void * for the > > ucontext argument, I've generally assumed that is not > > sufficient to get ucontext_t (or mcontext_t) (but maybe I'm too paranoid > > there). > > http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/signal.h.html > > "The header shall define the ucontext_t type as a structure > that shall include at least the following members: > ... > mcontext_t uc_mcontext A machine-specific representation of the saved > context." > > so signal.h must define ucontext_t but mcontext_t can be opaque. > (it is opaque with posix conform feature tests to avoid > namespace pollution, but with _GNU_SOURCE defined all > asm/sigcontext.h apis are there and mcontext_t matches > struct sigcontext) I see. Sounds reasonable. > > > > Non-POSIX-flavoured software might include directly. > > In glibc/musl libc will that conflict with , or can the two > > coexist? > > if you compile e.g in standard conform mode then > i think signal.h and asm/sigcontext.h are compatible. So long as we don't break any existing usage (?) I guess this is fine. Cheers ---Dave _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel