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 5F9D7C3DA79 for ; Mon, 15 Jan 2024 14:48:33 +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=Cbp/gtrW8pS8tldVHxTsADd2SAJAjy/2LXSs7twUQ54=; b=wqqCzokksSEcA2 PBd+NfFEwqItrrYNk60alavGt8uG+Cf62mpvvsw7hVi1lKOZ1fpuHPr6h8gnIX+5zKCB4NmxSDQSN k2QPU3fXW4p1P/3nYq6W/AGU+L30NK0wYBVQ4yH5ABJSTooplOGE9gyDwT9EbmjK0b74wOoSpeHeE NcwFwtRffOte5dPs/AUoIqhktIxE2vYvXf2tqJGF7N2g1M5EGCEYaLvXxe6HR+wdh3UfrM49Uk8rG Ysfcr5/va4QaB+6UBqtdDU0Lk5/ktCkyX4s85uTPo7kxdNB61r1mOF7Fm7L775TWMDGt2wR+sOHlH myEHtZ5ufAIiGgC8YVGg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rPOFz-009HrC-0R; Mon, 15 Jan 2024 14:48:07 +0000 Received: from out-181.mta1.migadu.com ([95.215.58.181]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rPOFw-009Hoz-0O for linux-arm-kernel@lists.infradead.org; Mon, 15 Jan 2024 14:48:06 +0000 Date: Mon, 15 Jan 2024 14:47:54 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1705330079; 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=70gQbu/giMgMkf4XDme2+PvJ3v9UrOA9656rWrCyjgc=; b=jADQY+aVG6V1M1+JSosgf/4FbPMNq0qEkomdtCuRkhoJjLA6ByHC5wE/Ks7JMP4XtYKpWH iL8ltxfsg/AbK4Ldf4Tb1l0GdsuYrG5zteM2dFMJB1q8DY8k0Y7DkZ4/UlScefpV5mQdW8 6mNT7mUFP8OzaSoLXXdMfpcEJuWxMw4= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: Marc Zyngier Cc: Ruidong Tian , kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org Subject: Re: [PATCH] KVM: arm64: Add missing ERX*_EL1 registers Message-ID: References: <20240110075739.8291-1-tianruidong@linux.alibaba.com> <867ckh9y7l.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <867ckh9y7l.wl-maz@kernel.org> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240115_064804_586007_45011630 X-CRM114-Status: UNSURE ( 8.45 ) X-CRM114-Notice: Please train this message. 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="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 10, 2024 at 12:20:30PM +0000, Marc Zyngier wrote: > If my reading of the ARM ARM is correct, these registers only exist if > FEAT_RASv1p1 is implemented. Which means that we shouldn't handle > those as RAZ/WI unconditionally, but instead check for what we > advertise to the guest and handle it accordingly. Can we go a step further and just stop advertising RAS to guests? I don't expect VMs to gain much from our RAZ/WI implementation. Conditional RAZ/WI would still be helpful in this case for migrated VMs that have 'seen' the feature. -- Thanks, Oliver _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel