From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 698242F22 for ; Fri, 11 Feb 2022 16:40:06 +0000 (UTC) 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-160-wZ1-VjIMOoK4So3RgiPxRg-1; Fri, 11 Feb 2022 16:40:03 +0000 X-MC-Unique: wZ1-VjIMOoK4So3RgiPxRg-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 15.0.1497.28; Fri, 11 Feb 2022 16:40:01 +0000 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.028; Fri, 11 Feb 2022 16:40:01 +0000 From: David Laight To: 'Bill Wendling' , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "x86@kernel.org" , "H . Peter Anvin" , Nathan Chancellor , "Nick Desaulniers" , Juergen Gross , Peter Zijlstra , Andy Lutomirski , "llvm@lists.linux.dev" CC: "linux-kernel@vger.kernel.org" Subject: RE: [PATCH v4] x86: use builtins to read eflags Thread-Topic: [PATCH v4] x86: use builtins to read eflags Thread-Index: AQHYHs4TBErQZHLpBUiy6+9ZW5FRHqyOjNCA Date: Fri, 11 Feb 2022 16:40:01 +0000 Message-ID: References: <20220204005742.1222997-1-morbo@google.com> <20220210223134.233757-1-morbo@google.com> In-Reply-To: <20220210223134.233757-1-morbo@google.com> 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] Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: 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 RnJvbTogQmlsbCBXZW5kbGluZw0KPiBTZW50OiAxMCBGZWJydWFyeSAyMDIyIDIyOjMyDQo+IA0K PiBHQ0MgYW5kIENsYW5nIGJvdGggaGF2ZSBidWlsdGlucyB0byByZWFkIGFuZCB3cml0ZSB0aGUg RUZMQUdTIHJlZ2lzdGVyLg0KPiBUaGlzIGFsbG93cyB0aGUgY29tcGlsZXIgdG8gZGV0ZXJtaW5l IHRoZSBiZXN0IHdheSB0byBnZW5lcmF0ZSB0aGlzDQo+IGNvZGUsIHdoaWNoIGNhbiBpbXByb3Zl IGNvZGUgZ2VuZXJhdGlvbi4NCj4gDQo+IFRoaXMgaXNzdWUgYXJvc2UgZHVlIHRvIENsYW5nJ3Mg aXNzdWUgd2l0aCB0aGUgIj1ybSIgY29uc3RyYWludC4gIENsYW5nDQo+IGNob29zZXMgdG8gYmUg Y29uc2VydmF0aXZlIGluIHRoZXNlIHNpdHVhdGlvbnMsIGFuZCBzbyB1c2VzIG1lbW9yeQ0KPiBp bnN0ZWFkIG9mIHJlZ2lzdGVycy4gVGhpcyBpcyBhIGtub3duIGlzc3VlLCB3aGljaCBpcyBjdXJy ZW50bHkgYmVpbmcNCj4gYWRkcmVzc2VkLg0KPiANCj4gSG93ZXZlciwgdXNpbmcgYnVpbHRpbnMg aXMgYmVuZWZpY2lhbCBpbiBnZW5lcmFsLCBiZWNhdXNlIGl0IHJlbW92ZXMgdGhlDQo+IGJ1cmRl biBvZiBkZXRlcm1pbmluZyB3aGF0J3MgdGhlIHdheSB0byByZWFkIHRoZSBmbGFncyByZWdpc3Rl ciBmcm9tIHRoZQ0KPiBwcm9ncmFtbWVyIGFuZCBwbGFjZXMgaXQgb24gdG8gdGhlIGNvbXBpbGVy LCB3aGljaCBoYXMgdGhlIGluZm9ybWF0aW9uDQo+IG5lZWRlZCB0byBtYWtlIHRoYXQgZGVjaXNp b24uDQoNCkV4Y2VwdCB0aGF0IG5laXRoZXIgZ2NjIG5vciBjbGFuZyBhdHRlbXB0IHRvIG1ha2Ug dGhhdCBkZWNpc2lvbi4NClRoZXkgYWx3YXlzIGRvIHB1c2hmOyBwb3AgYXg7DQoNCi4uLg0KPiB2 NDogLSBDbGFuZyBub3cgbm8gbG9uZ2VyIGdlbmVyYXRlcyBzdGFjayBmcmFtZXMgd2hlbiB1c2lu ZyB0aGVzZSBidWlsdGlucy4NCj4gICAgIC0gQ29ycmVjdGVkIG1pc3NwZWxsaW5ncy4NCg0KV2hp bGUgY2xhbmcgJ2hlYWQnIGhhcyBiZWVuIGZpeGVkLCBpdCBzZWVtcyBhIGJpdCBwcmVtYXR1cmUg dG8gc2F5DQppdCBpcyAnZml4ZWQnIGVub3VnaCBmb3IgYWxsIGNsYW5nIGJ1aWxkcyB0byB1c2Ug dGhlIGJ1aWx0aW4uDQoNClNlZW1zIGJldHRlciB0byBjaGFuZ2UgaXQgKGJhY2spIHRvICI9ciIg YW5kIGNvbW1lbnQgdGhhdCB0aGlzDQppcyBjdXJyZW50bHkgYXMgZ29vZCBhcyBfX2J1aWx0aW5f aWEzMl9yZWFkZWZsYWdzX3U2NCgpIGFuZCB0aGF0DQpjbGFuZyBtYWtlcyBhICdwaWdzIGJyZWFr ZmFzdCcgb2YgIj1ybSIgLSB3aGljaCBoYXMgb25seSBtYXJnaW5hbA0KYmVuZWZpdC4NCg0KQ2hh bmdpbmcgdG8gX19idWlsdGluX2lhMzJfcmVhZGVmbGFnc191NjQoKSBtYXkgYmUgd29ydGggd2hp bGUNCmlmL3doZW4gdGhlIGNvbXBpbGVycyB3aWxsIGdlbmVyYXRlIHB1c2hmOyBwb3AgbWVtOyBm b3IgaXQuDQoNCglEYXZpZA0KDQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1s ZXkgUm9hZCwgTW91bnQgRmFybSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJh dGlvbiBObzogMTM5NzM4NiAoV2FsZXMpDQo=