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 025DACA0FED for ; Tue, 9 Sep 2025 07:47:32 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=sS9KBzVCPbJWJWQ0UZ0j5q0+Yoxsvx3SirUPYIS2U7w=; b=T/OIB9d1W46kRTujSDD3IOZuT+ DzxyHxWo/pvTFsls/P+mMenVzMYLqr0YDTmJDzml9mznvjJiEftLoh6xW+wtSxU1Cf7ByIy19oiIg +p6RTc5wrBzHDatPodP2WuTqJiMk4NowFKYJWBQSjbanZeKmtka6eSyDFxwFLfKXUvPFtvFcaMXRf 5ZCESvOCchffVxrDmQ2RibnG+5haa1qyty3TPFkqfiPHwxoobMeSJap3ej85Jnlj4cTitOUT/+ZtO jMdjZCPiOG+cp5uS3VPNlvNV6bz1WoSir22EHXmKnPgLFekP/hGWYI7Avtfk5Ji7EdXdGdO7WRKKS U1UHqOVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uvt4V-00000005K6J-3TbS; Tue, 09 Sep 2025 07:47:23 +0000 Received: from out-173.mta1.migadu.com ([95.215.58.173]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uvsLX-000000050y8-2zjT for linux-arm-kernel@lists.infradead.org; Tue, 09 Sep 2025 07:00:57 +0000 Date: Tue, 9 Sep 2025 00:00:29 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1757401253; 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=sS9KBzVCPbJWJWQ0UZ0j5q0+Yoxsvx3SirUPYIS2U7w=; b=r3cdzDZcXKNh1ojPr0RNT8j7PkCqsztCRReeScRBIXigTRwrHQzCqgNV1zlusFoXRvpTUp bkd3wy/xGi0tFJNQXWn/bGYskpEVuq5v5jff5QslEy7u/c68ET842FIB7DAXkUmkVuxf3B U22VPhQz8M8BEg7jBu2ccv6ysABXPR8= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: Jinqian Yang Cc: yuzenghui@huawei.com, maz@kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, liuyonglong@huawei.com, wangzhou1@hisilicon.com Subject: Re: [PATCH v2 0/3] KVM: arm64: make EL2 feature fields writable in ID_AA64MMFR1_EL1 Message-ID: References: <20250909034415.3822478-1-yangjinqian1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250909034415.3822478-1-yangjinqian1@huawei.com> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250909_000055_904714_73D1DC39 X-CRM114-Status: UNSURE ( 9.01 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Sep 09, 2025 at 11:44:12AM +0800, Jinqian Yang wrote: > Allow userspace to downgrade EL2 features (VH, TWED, HCX) to ensure VM live > migration compatibility between hosts with varying feature support. > > v1: https://lore.kernel.org/linux-arm-kernel/20250325121126.1380681-1-yangjinqian1@huawei.com/ > > Change Log: > v1->v2: > -Added support for downgrading TWED and VH fields. > -Added corresponding test cases to the set_id_regs selftest. > > Jinqian Yang (3): > KVM: arm64: Make ID_AA64MMFR1_EL1.HCX writable from userspace > KVM: arm64: Make ID_AA64MMFR1_EL1.TWED writable from userspace > KVM: arm64: Make ID_AA64MMFR1_EL1.VH writable from userspace > > arch/arm64/kvm/sys_regs.c | 3 --- > tools/testing/selftests/kvm/arm64/set_id_regs.c | 3 +++ General comment: please make do kernel and selftest changes in separate patches. Thanks, Oliver