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[2620:137:e000::1:18]) by mx.google.com with ESMTPS id a8-20020a170902ecc800b00153b2d16408si1146099plh.16.2022.04.07.16.53.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Apr 2022 16:53:29 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18; Authentication-Results: mx.google.com; dkim=pass header.i=@zx2c4.com header.s=20210105 header.b=c16yF8ew; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=zx2c4.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 9820A149D32; Thu, 7 Apr 2022 16:22:03 -0700 (PDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232505AbiDGXX7 (ORCPT + 99 others); Thu, 7 Apr 2022 19:23:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231713AbiDGXX4 (ORCPT ); Thu, 7 Apr 2022 19:23:56 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87F2D107816 for ; Thu, 7 Apr 2022 16:21:54 -0700 (PDT) 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 238BF612DF for ; Thu, 7 Apr 2022 23:21:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE444C385A0; Thu, 7 Apr 2022 23:21:52 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="c16yF8ew" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1649373711; 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: in-reply-to:in-reply-to:references:references; bh=R1hw3ZaUnlA/kb6IATAoV5F47fVM3GAcXC3l10wss9Y=; b=c16yF8ewETCp8NjMxhD07+ZQF5RkOPbs+TgeaZxQjWY9SsmP+5DPYOZLf1saJDKk/yrUY8 a8WST2YvjBbFuMDNxH2vbwyuHzAO0UAM9u5gnpaESROaOxqP9OkSSbqFcTwN4pT31NhSKY C+ljnebBdh3sQ6EoYCcxMJ3OTzG7qJ0= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id e5a93b82 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Thu, 7 Apr 2022 23:21:51 +0000 (UTC) Date: Fri, 8 Apr 2022 01:21:41 +0200 From: "Jason A. Donenfeld" To: Hugh Dickins Cc: Borislav Petkov , Peter Zijlstra , linux-kernel@vger.kernel.org, x86@kernel.org, ak@linux.intel.com, Matthew Wilcox Subject: Re: x86: should clear_user() have alternatives? Message-ID: References: <2f5ca5e4-e250-a41c-11fb-a7f4ebc7e1c9@google.com> <9d3b36e9-f752-22bd-4ea3-cf169fa26e9b@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <9d3b36e9-f752-22bd-4ea3-cf169fa26e9b@google.com> X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE,T_SCC_BODY_TEXT_LINE, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey folks, Just a reminder that Samuel already did a lot of work and benchmarking and made this a lot faster: https://lore.kernel.org/lkml/20210523180423.108087-1-sneves@dei.uc.pt/ As far as I can tell, there was a lot of nitpicking, some of which might have been pointless, and the author understandably didn't followup to finish it off. But the code and analysis is there, and maybe it'd be worthwhile for somebody here to pick it up again? Jason