From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A05EC212FA0 for ; Wed, 10 Sep 2025 01:42:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757468558; cv=none; b=COxXab4EFEO5O8Eu8GAO1+PsarLYyaBUZQC9DGzMhbHSXyhpL3qsZw87z6XtsUK3xf90Gvn226SYokY2PXT9UcsqqVQVNWyhUliFjz+wAnFhyrKjT+TTeN2kPOx9XcgyqCb/5TxiRMm9UTB9zZ2mlmruEPOp6iC4PWwhXHkmjsA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757468558; c=relaxed/simple; bh=h5ic6/9akUbwtAWeg2F7MKdX9r1RkY/8JNuc6bC+cjw=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=YFtqpsk+vxw4fTaYv01iO54hBj8Lkp7eKaV2NDedtm/th7yQfXIo3zbjbEgDd9FGTqL0L+mexmsDfeJ3cFKCZULZuI1vRhBtLhPVGL715G0RRAAeHjowBakQfiONHcssxQdHjYKnGWOuNUYHn0V62uI/EZ5k9oCYb0ikmESfo/s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4cM3Gs2y4DzRk6r; Wed, 10 Sep 2025 09:37:57 +0800 (CST) Received: from dggpemf500013.china.huawei.com (unknown [7.185.36.188]) by mail.maildlp.com (Postfix) with ESMTPS id 63692180491; Wed, 10 Sep 2025 09:42:34 +0800 (CST) Received: from [10.67.121.183] (10.67.121.183) by dggpemf500013.china.huawei.com (7.185.36.188) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 10 Sep 2025 09:42:33 +0800 Message-ID: <6a1ec9d7-f41b-4ea2-a42c-26eec9591195@huawei.com> Date: Wed, 10 Sep 2025 09:42:32 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 0/3] KVM: arm64: make EL2 feature fields writable in ID_AA64MMFR1_EL1 To: Oliver Upton CC: , , , , , , References: <20250909034415.3822478-1-yangjinqian1@huawei.com> From: Jinqian Yang In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems100002.china.huawei.com (7.221.188.206) To dggpemf500013.china.huawei.com (7.185.36.188) On 2025/9/9 15:00, Oliver Upton wrote: > 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. > Will be changed in v3. Thanks, Jinqian