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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6C7AC433FE for ; Wed, 20 Apr 2022 07:32:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359848AbiDTHfD (ORCPT ); Wed, 20 Apr 2022 03:35:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359818AbiDTHe4 (ORCPT ); Wed, 20 Apr 2022 03:34:56 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.86.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 95AF63B57B for ; Wed, 20 Apr 2022 00:32:07 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-165-jcx-0iaIPGatONrL5yGJ_Q-1; 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Wed, 20 Apr 2022 07:32:51 +0000 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nh4os-007mcM-Gc for linux-riscv@lists.infradead.org; Wed, 20 Apr 2022 07:32:12 +0000 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-165-jcx-0iaIPGatONrL5yGJ_Q-1; Wed, 20 Apr 2022 08:32:04 +0100 X-MC-Unique: jcx-0iaIPGatONrL5yGJ_Q-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.32; Wed, 20 Apr 2022 08:32:02 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.033; Wed, 20 Apr 2022 08:32:02 +0100 From: David Laight To: 'He Zhe' , Kees Cook CC: "catalin.marinas@arm.com" , "will@kernel.org" , "mark.rutland@arm.com" , "tglx@linutronix.de" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "alexander.shishkin@linux.intel.com" , "jolsa@kernel.org" , "namhyung@kernel.org" , "benh@kernel.crashing.org" , "paulus@samba.org" , "borntraeger@linux.ibm.com" , "svens@linux.ibm.com" , "hpa@zytor.com" , "x86@kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-riscv@lists.infradead.org" , "linux-s390@vger.kernel.org" , "linux-perf-users@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Topic: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Index: AQHYU/YpuaYuTiSSXEqj2VkDLnuG5qz4aD5A Date: Wed, 20 Apr 2022 07:32:01 +0000 Message-ID: <9e5c394e82ec44e1887ebebe777a97f2@AcuMS.aculab.com> References: <20220418132217.1573072-1-zhe.he@windriver.com> <20220418132217.1573072-3-zhe.he@windriver.com> <202204181457.9DE190CE@keescook> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220420_003210_861284_D318D572 X-CRM114-Status: UNSURE ( 8.11 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org > > Thanks for doing this implementation! One reason usercopy hardening > > didn't persue doing a "full" stacktrace was because it seemed relatively > > expensive. Did you do any usercopy-heavily workload testing to see if > > there was a noticeable performance impact? Look at anything that uses sendmsg(). It is noticeably more expensive than sendto(). All the extra copy_from_user() cause measurable slow slowdowns. Using __copy_from_user()(to avoid 'hardending') in the socket code and when reading the iov[] gives a measurable improvement. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales) _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 24830C433EF for ; Wed, 20 Apr 2022 07:33:53 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4KjsqM2kt6z3bZf for ; Wed, 20 Apr 2022 17:33:51 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=aculab.com (client-ip=185.58.85.151; 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Wed, 20 Apr 2022 08:32:02 +0100 From: David Laight To: 'He Zhe' , Kees Cook Subject: RE: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Topic: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Index: AQHYU/YpuaYuTiSSXEqj2VkDLnuG5qz4aD5A Date: Wed, 20 Apr 2022 07:32:01 +0000 Message-ID: <9e5c394e82ec44e1887ebebe777a97f2@AcuMS.aculab.com> References: <20220418132217.1573072-1-zhe.he@windriver.com> <20220418132217.1573072-3-zhe.he@windriver.com> <202204181457.9DE190CE@keescook> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 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: "mark.rutland@arm.com" , "linux-s390@vger.kernel.org" , "x86@kernel.org" , "hpa@zytor.com" , "alexander.shishkin@linux.intel.com" , "catalin.marinas@arm.com" , "dave.hansen@linux.intel.com" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , "linux-perf-users@vger.kernel.org" , "bp@alien8.de" , "svens@linux.ibm.com" , "jolsa@kernel.org" , "namhyung@kernel.org" , "tglx@linutronix.de" , "borntraeger@linux.ibm.com" , "will@kernel.org" , "linux-riscv@lists.infradead.org" , "paulus@samba.org" , "linux-arm-kernel@lists.infradead.org" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" PiA+IFRoYW5rcyBmb3IgZG9pbmcgdGhpcyBpbXBsZW1lbnRhdGlvbiEgT25lIHJlYXNvbiB1c2Vy Y29weSBoYXJkZW5pbmcNCj4gPiBkaWRuJ3QgcGVyc3VlIGRvaW5nIGEgImZ1bGwiIHN0YWNrdHJh Y2Ugd2FzIGJlY2F1c2UgaXQgc2VlbWVkIHJlbGF0aXZlbHkNCj4gPiBleHBlbnNpdmUuIERpZCB5 b3UgZG8gYW55IHVzZXJjb3B5LWhlYXZpbHkgd29ya2xvYWQgdGVzdGluZyB0byBzZWUgaWYNCj4g PiB0aGVyZSB3YXMgYSBub3RpY2VhYmxlIHBlcmZvcm1hbmNlIGltcGFjdD8NCg0KTG9vayBhdCBh bnl0aGluZyB0aGF0IHVzZXMgc2VuZG1zZygpLg0KSXQgaXMgbm90aWNlYWJseSBtb3JlIGV4cGVu c2l2ZSB0aGFuIHNlbmR0bygpLg0KQWxsIHRoZSBleHRyYSBjb3B5X2Zyb21fdXNlcigpIGNhdXNl IG1lYXN1cmFibGUgc2xvdyBzbG93ZG93bnMuDQpVc2luZyBfX2NvcHlfZnJvbV91c2VyKCkodG8g YXZvaWQgJ2hhcmRlbmRpbmcnKSBpbiB0aGUgc29ja2V0IGNvZGUNCmFuZCB3aGVuIHJlYWRpbmcg dGhlIGlvdltdIGdpdmVzIGEgbWVhc3VyYWJsZSBpbXByb3ZlbWVudC4NCg0KCURhdmlkDQoNCi0N ClJlZ2lzdGVyZWQgQWRkcmVzcyBMYWtlc2lkZSwgQnJhbWxleSBSb2FkLCBNb3VudCBGYXJtLCBN aWx0b24gS2V5bmVzLCBNSzEgMVBULCBVSw0KUmVnaXN0cmF0aW9uIE5vOiAxMzk3Mzg2IChXYWxl cykNCg== 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 7B3C4C433FE for ; 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Wed, 20 Apr 2022 07:32:40 +0000 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nh4os-007mcJ-Gf for linux-arm-kernel@lists.infradead.org; Wed, 20 Apr 2022 07:32:12 +0000 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-165-jcx-0iaIPGatONrL5yGJ_Q-1; Wed, 20 Apr 2022 08:32:04 +0100 X-MC-Unique: jcx-0iaIPGatONrL5yGJ_Q-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.32; Wed, 20 Apr 2022 08:32:02 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.033; Wed, 20 Apr 2022 08:32:02 +0100 From: David Laight To: 'He Zhe' , Kees Cook CC: "catalin.marinas@arm.com" , "will@kernel.org" , "mark.rutland@arm.com" , "tglx@linutronix.de" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "alexander.shishkin@linux.intel.com" , "jolsa@kernel.org" , "namhyung@kernel.org" , "benh@kernel.crashing.org" , "paulus@samba.org" , "borntraeger@linux.ibm.com" , "svens@linux.ibm.com" , "hpa@zytor.com" , "x86@kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-riscv@lists.infradead.org" , "linux-s390@vger.kernel.org" , "linux-perf-users@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Topic: [PATCH RFC 2/8] arm64: stacktrace: Add arch_within_stack_frames Thread-Index: AQHYU/YpuaYuTiSSXEqj2VkDLnuG5qz4aD5A Date: Wed, 20 Apr 2022 07:32:01 +0000 Message-ID: <9e5c394e82ec44e1887ebebe777a97f2@AcuMS.aculab.com> References: <20220418132217.1573072-1-zhe.he@windriver.com> <20220418132217.1573072-3-zhe.he@windriver.com> <202204181457.9DE190CE@keescook> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220420_003210_875597_E47C011E X-CRM114-Status: UNSURE ( 9.11 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org > > Thanks for doing this implementation! One reason usercopy hardening > > didn't persue doing a "full" stacktrace was because it seemed relatively > > expensive. Did you do any usercopy-heavily workload testing to see if > > there was a noticeable performance impact? Look at anything that uses sendmsg(). It is noticeably more expensive than sendto(). All the extra copy_from_user() cause measurable slow slowdowns. Using __copy_from_user()(to avoid 'hardending') in the socket code and when reading the iov[] gives a measurable improvement. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel