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 E82BFC43334 for ; Tue, 19 Jul 2022 08:26:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235196AbiGSI0n (ORCPT ); Tue, 19 Jul 2022 04:26:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231645AbiGSI0k (ORCPT ); Tue, 19 Jul 2022 04:26:40 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 922DA21F for ; Tue, 19 Jul 2022 01:26:39 -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-136-8aiBKALHMe-YeGLl3g-g9w-1; Tue, 19 Jul 2022 09:26:36 +0100 X-MC-Unique: 8aiBKALHMe-YeGLl3g-g9w-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 15.0.1497.36; Tue, 19 Jul 2022 09:26:35 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.036; Tue, 19 Jul 2022 09:26:35 +0100 From: David Laight To: 'Linus Torvalds' , Thomas Gleixner CC: Sami Tolvanen , Joao Moreira , Peter Zijlstra , LKML , the arch/x86 maintainers , Tim Chen , Josh Poimboeuf , "Cooper, Andrew" , Pawan Gupta , Johannes Wikner , Alyssa Milburn , Jann Horn , "H.J. Lu" , "Moreira, Joao" , "Nuzman, Joseph" , "Steven Rostedt" , "Gross, Jurgen" , "Masami Hiramatsu" , Alexei Starovoitov , "Daniel Borkmann" , Peter Collingbourne Subject: RE: [patch 00/38] x86/retbleed: Call depth tracking mitigation Thread-Topic: [patch 00/38] x86/retbleed: Call depth tracking mitigation Thread-Index: AQHYmwK9i03gNC/QIkePUsvbFv4MOq2FWkvA Date: Tue, 19 Jul 2022 08:26:35 +0000 Message-ID: <0e038c2795784b7eb4de52f77b67206a@AcuMS.aculab.com> References: <20220716230344.239749011@linutronix.de> <87wncauslw.ffs@tglx> <87tu7euska.ffs@tglx> <87o7xmup5t.ffs@tglx> <87lesqukm5.ffs@tglx> <2f7f899cb75b79b08b0662ff4d2cb877@overdrivepizza.com> <87fsiyuhyz.ffs@tglx> 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogTGludXMgVG9ydmFsZHMNCj4gU2VudDogMTkgSnVseSAyMDIyIDAxOjAyDQo+IA0KPiBP biBNb24sIEp1bCAxOCwgMjAyMiBhdCA0OjUyIFBNIExpbnVzIFRvcnZhbGRzDQo+IDx0b3J2YWxk c0BsaW51eC1mb3VuZGF0aW9uLm9yZz4gd3JvdGU6DQo+ID4NCj4gPiBIb25lc3RseSwgSSB0aGlu ayB0aGF0IHdvdWxkIGJlIGEgYmV0dGVyIG1vZGVsIC0geWVzLCB5b3UgbG9zZSA4IGJpdHMNCj4g PiBvZiBoYXNoLCBidXQgY29uc2lkZXJpbmcgdGhhdCBhcHBhcmVudGx5IHRoZSBjdXJyZW50IEtD RkkgY29kZQ0KPiA+ICpndWFyYW50ZWVzKiB0aGF0IHRoZSBoYXNoIHBhdHRlcm4gd2lsbCBleGlz dCBldmVuIG91dHNpZGUgdGhlIGFjdHVhbA0KPiA+IHRhcmdldCBwYXR0ZXJuLA0KPiANCj4gR2Fh aCwgSSdtIGJlaW5nIHN0dXBpZCwuIFlvdSBzdGlsbCBnZXQgdGhlIHZhbHVlIGNvbGxpc2lvbiwg c2luY2UgdGhlDQo+IGludDMgYnl0ZSBwYXR0ZXJuIHdvdWxkIGp1c3QgYmUgcGFydCBvZiB0aGUg Y29tcGFyZSBwYXR0ZXJuLg0KPiANCj4gWW91J2QgaGF2ZSB0byB1c2Ugc29tZSBtdWx0aS1pbnN0 cnVjdGlvbiBjb21wYXJlIHRvIGF2b2lkIGhhdmluZyB0aGUNCj4gcGF0dGVybiBpbiB0aGUgaW5z dHJ1Y3Rpb24gc3RyZWFtLiBQcm9iYWJseSB3aXRoIGFub3RoZXIgcmVnaXN0ZXIuDQo+IExpa2UN Cj4gDQo+ICAgICAgICAgbW92bCAtRklYRURfT0ZGU0VUKCVlYXgpLCVyZHgNCj4gICAgICAgICBh ZGRsICRBTlRJX1BBVFRFUk4sJXJkeA0KPiAgICAgICAgIGplIG9rDQo+IA0KPiBzbyB0aGF0IHRo ZSAiY29tcGFyZSIgd291bGRuJ3QgdXNlIHRoZSBzYW1lIHBhdHRlcm4gdmFsdWUsIGJ1dCBiZSBh bg0KPiBhZGQgd2l0aCB0aGUgbmVnYXRlZCBwYXR0ZXJuIHZhbHVlIGluc3RlYWQuDQo+IA0KPiBU aGUgZXh0cmEgaW5zdHJ1Y3Rpb24gaXMgbGlrZWx5IGxlc3Mgb2YgYSBwcm9ibGVtIHRoYW4gdGhl IGV4dHJhIHJlZ2lzdGVyIHVzZWQuDQoNClNob3VsZG4ndCBpdCBiZSB0ZXN0aW5nIHRoZSB2YWx1 ZSB0aGUgY2FsbGVyIHN1cHBsaWVkPw0KDQpUaGUgZXh0cmEgaW5zdHJ1Y3Rpb24gaXMgbGlrZWx5 IHRvIGJlIG9uZSBjbG9jayAtIEkgZG91YnQgaXQgd2lsbA0Kc2Vuc2libHkgcnVuIGluIHBhcmFs bGVsIHdpdGggY29kZSBsYXRlciBpbiB0aGUgZnVuY3Rpb24uDQoNClRoZSBsYXJnZXIgY29zdHMg YXJlIChwcm9iYWJseSkgcG9sbHV0aW5nIHRoZSBEJCB3aXRoIEkgYWRkcmVzc2VzDQooYWxyZWFk eSBkb25lIGJ5IHRoZSBjYWxsZXIpIGFuZCB0aGUgbGlrZWx5IG1pc3ByZWRpY3RlZCAnamUgb2sn Lg0KVW5sZXNzIHRoZSBmdW5jdGlvbiBoYXMgYmVlbiByZWNlbnRseSBjYWxsZWQgdGhlICdqZSBv aycgZ2V0cw0Kc3RhdGljIHByZWRpY3Rpb24uDQpXaGlsZSB0cmFkaXRpb25hbGx5IHRoYXQgd291 bGQgcHJlZGljdCBhIGZvcndhcmRzIGJyYW5jaCAnbm90IHRha2VuJw0KSVNUUiBtb3JlIHJlY2Vu dCBJbnRlbCBjcHUganVzdCB1c2UgdGhlIHByZWRpY3RvciBvdXRwdXQgLSBpZSByYW5kb20uDQpO b3QgYXQgYWxsIHN1cmUgYWJvdXQgQU1EIGNwdSB0aG91Z2guDQoNCglEYXZpZA0KDQotDQpSZWdp c3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFybSwgTWlsdG9u IEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAoV2FsZXMpDQo=