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 3BAE3C433EF for ; Thu, 21 Jul 2022 22:01:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233985AbiGUWBV (ORCPT ); Thu, 21 Jul 2022 18:01:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233557AbiGUWBT (ORCPT ); Thu, 21 Jul 2022 18:01:19 -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 148451759B for ; Thu, 21 Jul 2022 15:01:17 -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-146-vVf4_H80MfeFo66gwMM5tg-1; Thu, 21 Jul 2022 23:01:15 +0100 X-MC-Unique: vVf4_H80MfeFo66gwMM5tg-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; Thu, 21 Jul 2022 23:01:12 +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; Thu, 21 Jul 2022 23:01:12 +0100 From: David Laight To: 'Linus Torvalds' , Peter Zijlstra CC: Sami Tolvanen , Thomas Gleixner , Joao Moreira , 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 , Kees Cook Subject: RE: [patch 00/38] x86/retbleed: Call depth tracking mitigation Thread-Topic: [patch 00/38] x86/retbleed: Call depth tracking mitigation Thread-Index: AQHYnSyhi03gNC/QIkePUsvbFv4MOq2JW8MQ Date: Thu, 21 Jul 2022 22:01:12 +0000 Message-ID: References: <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 RnJvbTogTGludXMgVG9ydmFsZHMNCj4gU2VudDogMjEgSnVseSAyMDIyIDE5OjA3DQouLi4NCj4g IChiKSBzaW5jZSB5b3UgaGF2ZSB0aGF0IHIxMCB1c2UgYW55d2F5LCB3aHkgY2FuJ3QgeW91IGp1 c3QgZ2VuZXJhdGUgdGhlIHNpbXBsZXINCj4gDQo+ICAgICAgICAgbW92bCAkLUlNTSwlcjEwZA0K PiAgICAgICAgIGFkZGwgLTQoJWNhbGxkZXN0KSwlcjEwZA0KPiANCj4gICAgICBpbnN0ZWFkPyBZ b3Ugb25seSBuZWVkIFpGIGFueXdheS4NCj4gDQo+ICAgICAgTWF5YmUgeW91IG5lZWQgdG8gYWRk IHNvbWUgInIxMCBpcyBjbG9iYmVyZWQiIHRoaW5nLCBJIGRvbid0IGtub3cuDQo+IA0KPiBCdXQg YWdhaW46IEkgZG9uJ3Qga25vdyBsbHZtLCBzbyB0aGUgYWJvdmUgaXMgYmFzaWNhbGx5IG1lIGp1 c3QgZG9pbmcNCj4gdGhlICJwYXR0ZXJuIG1hdGNoaW5nIG1vbmtleSIgdGhpbmcuDQo+IA0KPiAg ICAgICAgICAgICAgTGludXMNCg0KU2luY2U6ICJJZiB0aGUgY2FsbGVlIGlzIGEgdmFyaWFkaWMg ZnVuY3Rpb24sIHRoZW4gdGhlIG51bWJlciBvZiBmbG9hdGluZw0KcG9pbnQgYXJndW1lbnRzIHBh c3NlZCB0byB0aGUgZnVuY3Rpb24gaW4gdmVjdG9yIHJlZ2lzdGVycyBtdXN0IGJlIHByb3ZpZGVk DQpieSB0aGUgY2FsbGVyIGluIHRoZSBBTCByZWdpc3Rlci4iDQoNCkFuZCB0aGF0IHRoYXQgbmV2 ZXIgaGFwcGVucyBpbiB0aGUga2VybmVsIHlvdSBjYW4gdXNlICVlYXggaW5zdGVhZA0Kb2YgJXIx MGQuDQoNCkV2ZW4gaW4gdXNlcnNwYWNlICVhbCBjYW4gYmUgc2V0IG5vbi16ZXJvIGFmdGVyIHRo ZSBzaWduYXR1cmUgY2hlY2suDQoNCklmIHlvdSBhcmUgd2lsbGluZyB0byBjdXQgdGhlIHNpZ25h dHVyZSBkb3duIHRvIDI2IGJpdHMgYW5kDQp0aGVuIGVuc3VyZSB0aGF0IG9uZSBvZiB0aGUgYnl0 ZXMgb2YgLUlNTSAob3IgfklNTSBpZiB5b3UNCnVzZSB4b3IpIGlzIDB4Y2MgYW5kIGp1bXAgYmFj ayB0byB0aGF0IG9uIGVycm9yIHRoZSBjaGVjaw0KYmVjb21lczoNCgltb3ZsCSQtSU1NLCVlYXgN CjE6CWFkZGwJLTQoJWNhbGxkZXN0KSwlZWF4DQoJam56CTFiLTEJLy8gb3IgLTIsIC0zLCAtNA0K CWFkZAkkbnVtX2ZwX2FyZ3MsJWVheAkvLyBJZiBuZWVkZWQgbm9uLXplcm8NCgljYWxsCSVjYWxs ZGVzdA0KDQpJIHRoaW5rIHRoYXQgYWRkcyAxMCBieXRlcyB0byB0aGUgY2FsbCBzaXRlLg0KQWx0 aG91Z2ggd2l0aCByZXRwb2xpbmUgdGh1bmtzIChhbmQgbm8gZnAgdmFyYXJncyBjYWxscykNCmFs bCBidXQgdGhlIGluaXRpYWwgbW92bCBjYW4gZ28gaW50byB0aGUgdGh1bmsuDQoNCglEYXZpZA0K DQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFy bSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAo V2FsZXMpDQo=