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[209.132.180.67]) by mx.google.com with ESMTP id y4si11235478otk.219.2019.12.09.03.15.22; Mon, 09 Dec 2019 03:15:35 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727327AbfLILBg (ORCPT + 99 others); Mon, 9 Dec 2019 06:01:36 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([146.101.78.151]:55140 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727143AbfLILBf (ORCPT ); Mon, 9 Dec 2019 06:01:35 -0500 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-195-oi3zS5NyMcuX2OLZVzunJg-1; Mon, 09 Dec 2019 11:01:31 +0000 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 9 Dec 2019 11:01:30 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 9 Dec 2019 11:01:30 +0000 From: David Laight To: 'Eric Dumazet' , network dev , "x86@kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: recvfrom/recvmsg performance and CONFIG_HARDENED_USERCOPY Thread-Topic: recvfrom/recvmsg performance and CONFIG_HARDENED_USERCOPY Thread-Index: AdWsNynavvs+VRwOQ6mSStk+IzVA6AACUqqAAI3fO8A= Date: Mon, 9 Dec 2019 11:01:30 +0000 Message-ID: References: <23db23416d3148fa86e54dccc6152266@AcuMS.aculab.com> In-Reply-To: Accept-Language: en-GB, en-US Content-Language: 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 X-MC-Unique: oi3zS5NyMcuX2OLZVzunJg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogRXJpYyBEdW1hemV0DQo+IFNlbnQ6IDA2IERlY2VtYmVyIDIwMTkgMTQ6MjINCi4uLg0K PiBSZWFsIHF1ZXN0aW9uIGlzIDogRG8geW91IGFjdHVhbGx5IG5lZWQgdG8gdXNlIHJlY3Ztc2co KSBpbnN0ZWFkIG9mIHJlY3Zmcm9tKCkgPw0KPiBJZiByZWN2bXNnKCkgcHJvdmlkZXMgYWRkaXRp b25hbCBjbXNnLCB0aGlzIGlzIG5vdCBzdXJwcmlzaW5nIGl0IGlzIG1vcmUgZXhwZW5zaXZlLg0K DQpFeGNlcHQgSSdtIG5vdCBwYXNzaW5nIGluIGEgYnVmZmVyIGZvciBpdC4NClRoZSByZWFzb24g SSdtIGxvb2tpbmcgYXQgcmVjdm1zZyBpcyB0aGF0IEknZCBsaWtlIHRvIHVzZSByZWN2bW1zZyBp dCBvcmRlciB0bw0KcmVhZCBvdXQgbW9yZSB0aGFuIG9uZSBtZXNzYWdlIGZyb20gYSBzb2NrZXQg d2l0aG91dCBkb2luZyBhbiBleHRyYSBwb2xsKCkuDQpOb3RlIHRoYXQgSSBkb24ndCBleHBlY3Qg dGhlcmUgdG8gYmUgYSBzZWNvbmQgbWVzc2FnZSBtb3N0IG9mIHRoZSB0aW1lIGFuZA0KYWxtb3N0 IG5ldmVyIGEgdGhpcmQgb25lLg0KDQpBbHRob3VnaCBJIHRoaW5rIHRoYXQgd2lsbCBvbmx5IGV2 ZXIgJ3dpbicgaWYgcmVjdm1tc2coKSBjYWxsZWQgdmZzX3BvbGwoKSB0byBmaW5kDQppZiB0aGVy ZSB3YXMgbW9yZSBkYXRhIHRvIHJlYWQgYmVmb3JlIGRvaW5nIGFueSBvZiB0aGUgY29weV9mcm9t X3VzZXIoKSBldGMuDQoNCj4gcmVjdm1zZygpIGFsc28gdXNlcyBhbiBpbmRpcmVjdCBjYWxsLCBz byBDT05GSUdfUkVUUE9MSU5FPXkgaXMgcHJvYmFibHkgaHVydGluZy4NCg0KSSBkb24ndCBoYXZl IENPTkZJR19SRVRQT0xJTkUgZW5hYmxlZCwgdGhlIGNvbXBpbGVyIEknbSB1c2luZyBpcyB0b28g b2xkLg0KKGdjYyA0LjcuMykuDQoNCglEYXZpZA0KDQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFr ZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFybSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwg VUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAoV2FsZXMpDQo=