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 9EDF4ECAAD2 for ; Mon, 29 Aug 2022 19:10:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XAadBqHK/ECxp2Wjsj78mbl7bLdc0Ufc+uYwjAKcoc8=; b=g7UjUJRhwXiu4m jtsDyusSh2ocS/EfO1bJWmkp0yB96mACma/1ra1//Gxn0YRdQ23IQw3Po24b3T5MjJRttkkTSU8fg g3+hj7iqNQY/Jmdlt788K4sF6ZpXd6yv/Rxi0QuddM+p/tXQZzjP2291Fs/FYmW6/DnG0XQZJlizT fxT0LBU2H4vUS5YumGoNJerF7K/RTMzsh59JdI4t6xalhnuVkf7GkP7UN62GFiytd6YvV+/O9YVtr xNwqqEea9rwZMgSxjaXPDfd6bzUyMsSMvLRxzTSDhL2N3CqIMOoN9X9yAJ/CSUxJTGd1u1hrZ+88/ zU0qNfI86b1TJNq7Ih9g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oSk8l-00CQVf-85; Mon, 29 Aug 2022 19:09:43 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oSk8h-00CQUH-8Z for linux-arm-kernel@lists.infradead.org; Mon, 29 Aug 2022 19:09:40 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 63ABB6136E; Mon, 29 Aug 2022 19:09:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 01A24C433C1; Mon, 29 Aug 2022 19:09:36 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="fxxJbh2C" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1661800175; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=se7iHVBPmFGtUkY2jW1ypnd8OsfvW6M/G2Rrn6yTXLg=; b=fxxJbh2CmEGHAFmQppyVLivVtInkWs+D4yIevizSiev6bXgUAUU1sNVOdtQRANPUecF1zA 1A3kCvGzbuHfFYxKjl45J1aD3UTeL6QaGEDyhyj/NmWRlkRDHESTCErFlK6lNEHIiba/pi 1IXCxdMFAko30+Sa+D1qzFRcshvTO1w= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 53fce227 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Mon, 29 Aug 2022 19:09:35 +0000 (UTC) Date: Mon, 29 Aug 2022 15:09:30 -0400 From: "Jason A. Donenfeld" To: Eric Biggers Cc: x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Adam Langley , Ard Biesheuvel Subject: Re: Should Linux set the new constant-time mode CPU flags? Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220829_120939_386971_D639F59C X-CRM114-Status: GOOD ( 20.06 ) 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="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gTW9uLCBBdWcgMjksIDIwMjIgYXQgMDY6MDg6MDdQTSArMDAwMCwgRXJpYyBCaWdnZXJzIHdy b3RlOgo+IEknZCBtdWNoIHByZWZlciBpdCBiZWluZyBzZXQgdW5jb25kaXRpb25hbGx5IGJ5IGRl ZmF1bHQgYXMgd2VsbCwgYXMgbWFraW5nCj4gZXZlcnlvbmUgKGJvdGgga2VybmVsIGFuZCB1c2Vy c3BhY2UpIHR1cm4gaXQgb24gYW5kIG9mZiBjb25zdGFudGx5IHdvdWxkIGJlIGEKPiBuaWdodG1h cmUuCj4gCj4gTm90ZSB0aGF0IEludGVsJ3MgZG9jdW1lbnRhdGlvbiBzYXlzIHRoYXQgQ1BVcyBi ZWZvcmUgSWNlIExha2UgYmVoYXZlIGFzIGlmCj4gRE9JVE0gaXMgYWx3YXlzIHNldDoKPiAKPiAg ICAgIkZvciBJbnRlbMKuIENvcmXihKIgZmFtaWx5IHByb2Nlc3NvcnMgYmFzZWQgb24gbWljcm9h cmNoaXRlY3R1cmVzIGJlZm9yZSBJY2UKPiAgICAgTGFrZSBhbmQgSW50ZWwgQXRvbcKuIGZhbWls eSBwcm9jZXNzb3JzIGJhc2VkIG9uIG1pY3JvYXJjaGl0ZWN0dXJlcyBiZWZvcmUKPiAgICAgR3Jh Y2Vtb250IHRoYXQgZG8gbm90IGVudW1lcmF0ZSBJQTMyX1VBUkNIX01JU0NfQ1RMLCBkZXZlbG9w ZXJzIG1heSBhc3N1bWUKPiAgICAgdGhhdCB0aGUgaW5zdHJ1Y3Rpb25zIGxpc3RlZCBoZXJlIG9w ZXJhdGUgYXMgaWYgRE9JVE0gaXMgZW5hYmxlZC4iCj4gCj4gKEl0J3MgYSBiaXQgYW1iaWd1b3Vz LCBhcyBpdCBsZWF2ZXMgdGhlIGRvb3Igb3BlbiB0byBJQTMyX1VBUkNIX01JU0NfQ1RMIGJlaW5n Cj4gcmV0cm9hY3RpdmVseSBhZGRlZCB0byBvbGQgQ1BVcy4gIEJ1dCBJIGFzc3VtZSB0aGF0IGhh c24ndCBhY3R1YWxseSBoYXBwZW5lZC4pCj4gCj4gU28gSSB0aGluayB0aGUgbG9naWNhbCBhcHBy b2FjaCBpcyB0byB1bmNvbmRpdGlvbmFsbHkgc2V0IERPSVRNIGJ5IGRlZmF1bHQsIHRvCj4gZml4 IHRoaXMgQ1BVIGJ1ZyBpbiBJY2UgTGFrZSBhbmQgbGF0ZXIgYW5kIGp1c3QgYnJpbmcgdGhpbmdz IGJhY2sgdG8gdGhlIHdheQo+IHRoZXkgd2VyZSBpbiBDUFVzIGJlZm9yZSBJY2UgTGFrZS4gIFdp dGggdGhhdCBhcyBhIGJhc2VsaW5lLCB3ZSBjYW4gdGhlbiBkaXNjdXNzCj4gd2hldGhlciBpdCdz IHVzZWZ1bCB0byBwcm92aWRlIHdheXMgdG8gcmUtZW5hYmxlIHRoaXMgQ1BVIGJ1ZyAvICJmZWF0 dXJlIiwgZm9yCj4gcGVvcGxlIHdobyB3YW50IHRvIGdldCB0aGUgcGVyZm9ybWFuY2UgYm9vc3Qg KGlmIG9uZSBhY3R1YWxseSBleGlzdHMpIG9mIGRhdGEKPiBkZXBlbmRlbnQgdGltaW5nIGFmdGVy IGNhcmVmdWxseSBhc3Nlc3NpbmcgdGhlIHJpc2tzLgo+IAo+IFRoZSBvdGhlciB3YXkgYXJvdW5k LCBvZiBtYWtpbmcgZXZlcnl0aGluZyBpbnNlY3VyZSBieSBkZWZhdWx0LCBzZWVtcyBsaWtlIGEK PiByZWFsbHkgYmFkIGlkZWEuCgpSaWdodC4gSXQncyBhY3R1YWxseSBraW5kIG9mIHN1cnByaXNp bmcgdGhhdCBJbnRlbCBkaWRuJ3QgYWxyZWFkeSBkbwp0aGlzIGJ5IGRlZmF1bHQuIFN1cmUsIG1h eWJlIHRoZSBJbnRlbCBtYW51YWwgbmV2ZXIgZXhwbGljaXRseQpndWFyYW50ZWVkIGNvbnN0YW50 IHRpbWUsIGJ1dCBhIGhlY2sgb2YgYSBsb3Qgb2YgY29kZSByZWxpZXMgb24gdGhhdApiZWluZyB0 aGUgY2FzZS4KCkphc29uCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fXwpsaW51eC1hcm0ta2VybmVsIG1haWxpbmcgbGlzdApsaW51eC1hcm0ta2VybmVsQGxp c3RzLmluZnJhZGVhZC5vcmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0 aW5mby9saW51eC1hcm0ta2VybmVsCg==