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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46E72C4724C for ; Thu, 30 Apr 2020 16:08:31 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 1D4982076D for ; Thu, 30 Apr 2020 16:08:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ph11GfMi"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="MrnXE3bh" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D4982076D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject: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=nUIAlC+8vibxaX5QVihPmVSzkEhHt0uTfAOMUnVFcsU=; b=ph11GfMix/LpR/ BB7U4xEjo0KR24Q8iXl8LqwHZgvFFyYOF9R4aEVetYoLFmsXdF28bOfGrVIIofxDNotsV64sDJUe7 /o8rcTf5E9W7F0uS6UdGCXqVZh9inDPU/0rNZ35jzEi63vh/dMaEA+7pmCLAvYbVG+62j3H0btaYD j9oDsqkj3P+a6yMrCavFJ3Sn1t5frMikRZL/OBlA+k8XLJgfsbIjZVO4GArm9ZF5K30P8ScGuhyD2 /OrmBIkhVdMvJkeTJ9/4kNrmoGfjWpc1XXFaWFBerESaYrxZBHGA/BrfbRDWs9wAdubpyZRaqBcDN PtTACh+G2OnrGE9rbbrA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jUBjg-0003Bt-H7; Thu, 30 Apr 2020 16:08:28 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jUBjd-0003BP-P6 for linux-arm-kernel@lists.infradead.org; Thu, 30 Apr 2020 16:08:26 +0000 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C66052076D; Thu, 30 Apr 2020 16:08:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588262905; bh=7bQtmp+LVEtku56Wh7klBkiOxfuNf/1bfIv2rQj7acY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MrnXE3bhXgFieK2gbsCzhRv4a61JYDHxFZCA1augf2biefQLgoLN1GYnICuvLxkts YaWrowcmLu7Y/ilLm2IW3stD+73AJk5hXJlWV+VW3oxt+2V7+avxXaxdau7QVTsw7H 6D4RDB0YMbxqeSMDEiTark35975NFArGwPmaOgzQ= Date: Thu, 30 Apr 2020 17:08:21 +0100 From: Will Deacon To: Mark Brown Subject: Re: [PATCH v2 1/3] arm64: insn: Don't assume unrecognized HINTs are NOPs Message-ID: <20200430160821.GC25258@willie-the-truck> References: <20200428172433.48830-1-broonie@kernel.org> <20200428172433.48830-2-broonie@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200428172433.48830-2-broonie@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200430_090825_839014_7B768870 X-CRM114-Status: GOOD ( 10.01 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Catalin Marinas , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Apr 28, 2020 at 06:24:31PM +0100, Mark Brown wrote: > Currently the kernel assumes that any HINT which it does not explicitly > recognise is a NOP. This is not robust as new instructions may be added > which need special handling, including recent extensions like PAC, and > in any case software should only be using explicit NOP instructions for > deliberate NOPs. Hmm, I'm not sure that using PAC as the justification makes tonnes of sense here, since you go ahead and whitelist the PAC hints in patch 3! Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel