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 96C20CA6007 for ; Thu, 8 Oct 2026 08:52:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xAFP0AVDCh2B4KtGCFjvZQtIzH5gDF6Ae8plAGWRgyM=; b=EsaQrivMULcP5mDjsuycx6n0qT WjXriQ0MmL7VdIgIX0G/QNygGf71oswyPYkE4uwRdQl3yIXJ++Qi292FXd2Oe3cJrcF5XLj3Atx9b VLN2Q7866xSvLdoaF56QRUCMotAXXLHEi7j5R+VFuGlBslC6B7P81qn7Wg/klYbUhzP/E7mL4HXtS xPLZnmfAqHUQCnBXS8LTci2quh9dtTDsjOZhhGKGIKCYiVdzcKaOcJKiQECzTZ5sbnPfXpVWSG0Df Dro8Bvu9sgURPnvNGaG48CPKQj7K/qM4MOsbWxxV0UJXGgHzT8sGLSmCq/8wehCFQgvy9hFFz26d9 UgAIFzpw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xEjrC-00000003vNK-2c9m; Thu, 08 Oct 2026 08:52:06 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xEjr9-00000003vMj-2X9z for linux-arm-kernel@lists.infradead.org; Thu, 08 Oct 2026 08:52:05 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B1C051476; Thu, 8 Oct 2026 01:51:57 -0700 (PDT) Received: from [10.57.10.184] (unknown [10.57.10.184]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BD5033F763; Thu, 8 Oct 2026 01:51:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1791449520; bh=X072fEuKl2pqebo1yIskiav4B6oQoevvlg9BJsl+1zA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=FcFOF6yov50M43gMq00NFQk0QAaBq1r/HTi+aauN8hylw6FtKWQFC3JnYMgpOMxpV p6yq7LD+lUNl//kIVCosM1EI9h1mB7tbiRmwoXAfDuO98j7UfJsSVtejyWHh++dv2v 3k6zBLtJOklseD1jlrbck3RHGUGr4ONIezBDHmmM= Message-ID: <4cdd882b-832f-4968-9838-dcc29a899121@arm.com> Date: Thu, 8 Oct 2026 09:51:56 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v23 13/14] KVM: arm64: Mandate VGIC v3 for pKVM VMs and Realms Content-Language: en-GB To: Fuad Tabba Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, gshan@redhat.com, joey.gouly@arm.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com, sudeep.holla@arm.com, jonathan.cameron@oss.qualcomm.com References: <20261007073537.2454351-1-suzuki.poulose@arm.com> <20261007073537.2454351-14-suzuki.poulose@arm.com> From: Suzuki K Poulose In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261008_015203_790812_15A2FE5C X-CRM114-Status: GOOD ( 13.38 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 07/10/2026 14:45, Fuad Tabba wrote: > Hi Suzuki, > > On Wed, 07 Oct 2026 08:35:36 +0100, Suzuki K Poulose > wrote: >> pKVM does not trust the host. Realm VMs follow a similar trust model, with >> the Realm Management Monitor owning the protected state instead of the >> host. Add a helper to identify VMs that run under a host-distrusting >> hypervisor. > > When I reviewed this in v21, the Realm patches that use this came > later in the same series. Without them, kvm_vm_hyp_is_distrusting() is > true exactly when is_protected_kvm_enabled() is, and protected mode > already doesn't register a GICv2, so this patch doesn't change > anything on its own. Should it move to the series that adds Realms? But the second part of the changes are required for pKVM today, right ? and you requested that here. The check as such is useful, except that it is using kvm_vm_hyp_is_distrusting() rather than is_protected_kvm_enabled(). I don't see this as a problem as this is not a hotpath anyway. https://lore.kernel.org/all/CA+EHjTzKjjEuAuoOuzGG0uKyVZE-r+CEreca2H2kEQYuRPpgUw@mail.gmail.com Cheers Suzuki> > Cheers, > /fuad