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=-14.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 5AB90C43461 for ; Mon, 14 Sep 2020 14:32:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2335A207EA for ; Mon, 14 Sep 2020 14:32:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600093937; bh=FJGrFZh/wSlG57bHCjvhePW4NhaqITwdnUviTd90E1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=v9CmyeF27ILNpPGK2Z5T0RXfv57TDo+inztDa2OxK/QNGiNkpSYfqpHNzsDj2Vdzs msMbrqiTJ6uGeBd5mENEAD31BefjhzNENEnd0iwGceRSNW2PFHmi4pt8FN+GM2h1aL UNayVFcdEPxPqlSq9WNltIaKTnXNQrc5Czk98CCA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726649AbgINNFv (ORCPT ); Mon, 14 Sep 2020 09:05:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:60290 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726616AbgINNF3 (ORCPT ); Mon, 14 Sep 2020 09:05:29 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 20DB32222A; Mon, 14 Sep 2020 13:04:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600088673; bh=FJGrFZh/wSlG57bHCjvhePW4NhaqITwdnUviTd90E1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IPZ84mhEoyRPga2DH98rhbeTd3HY/6eUSFUdJThfihiGwdYshpOmG2+csdig2XmBX AE21hP3lmmyk6aWqwdX/hoccOSdc2IERQQALwOoizmxdS0ZHtBVb4eaPVcecovi4d+ e+sqSsXlkAgLb56hbPvAoJEAwousK/EVzZ3fpK3E= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Huacai Chen , Paolo Bonzini , Sasha Levin , linux-mips@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH AUTOSEL 5.8 29/29] KVM: MIPS: Change the definition of kvm type Date: Mon, 14 Sep 2020 09:03:58 -0400 Message-Id: <20200914130358.1804194-29-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200914130358.1804194-1-sashal@kernel.org> References: <20200914130358.1804194-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Huacai Chen [ Upstream commit 15e9e35cd1dec2bc138464de6bf8ef828df19235 ] MIPS defines two kvm types: #define KVM_VM_MIPS_TE 0 #define KVM_VM_MIPS_VZ 1 In Documentation/virt/kvm/api.rst it is said that "You probably want to use 0 as machine type", which implies that type 0 be the "automatic" or "default" type. And, in user-space libvirt use the null-machine (with type 0) to detect the kvm capability, which returns "KVM not supported" on a VZ platform. I try to fix it in QEMU but it is ugly: https://lists.nongnu.org/archive/html/qemu-devel/2020-08/msg05629.html And Thomas Huth suggests me to change the definition of kvm type: https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg03281.html So I define like this: #define KVM_VM_MIPS_AUTO 0 #define KVM_VM_MIPS_VZ 1 #define KVM_VM_MIPS_TE 2 Since VZ and TE cannot co-exists, using type 0 on a TE platform will still return success (so old user-space tools have no problems on new kernels); the advantage is that using type 0 on a VZ platform will not return failure. So, the only problem is "new user-space tools use type 2 on old kernels", but if we treat this as a kernel bug, we can backport this patch to old stable kernels. Signed-off-by: Huacai Chen Message-Id: <1599734031-28746-1-git-send-email-chenhc@lemote.com> Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/mips/kvm/mips.c | 2 ++ include/uapi/linux/kvm.h | 5 +++-- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index 666d3350b4ac1..6c6836669ce16 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -137,6 +137,8 @@ extern void kvm_init_loongson_ipi(struct kvm *kvm); int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { switch (type) { + case KVM_VM_MIPS_AUTO: + break; #ifdef CONFIG_KVM_MIPS_VZ case KVM_VM_MIPS_VZ: #else diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 4fdf303165827..65fd95f9784ce 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -789,9 +789,10 @@ struct kvm_ppc_resize_hpt { #define KVM_VM_PPC_HV 1 #define KVM_VM_PPC_PR 2 -/* on MIPS, 0 forces trap & emulate, 1 forces VZ ASE */ -#define KVM_VM_MIPS_TE 0 +/* on MIPS, 0 indicates auto, 1 forces VZ ASE, 2 forces trap & emulate */ +#define KVM_VM_MIPS_AUTO 0 #define KVM_VM_MIPS_VZ 1 +#define KVM_VM_MIPS_TE 2 #define KVM_S390_SIE_PAGE_OFFSET 1 -- 2.25.1