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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 E4BC2C4CEC5 for ; Fri, 13 Sep 2019 13:14:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B41B2208C2 for ; Fri, 13 Sep 2019 13:14:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380451; bh=mUBQxfQ32UvOlvNiMiNAHQHwA17r2wn3WVj5j3Oj+fg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=vIt3Jk0XRR5l8ObN4bxllkeWZfnI6f5ip6e5SQad83uitp9a1MLOokXbTyUCoV+cf OUQGcF2/bry5F23ldZNjSRnYv/VV2gAfeJwG6tdYQ9I692dO3nMs07ebHnZStx/tG/ WqGC4b6m2OgujakasaypCzW253wQit9ZyJ6fv4ng= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388895AbfIMNOK (ORCPT ); Fri, 13 Sep 2019 09:14:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:39986 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388885AbfIMNOH (ORCPT ); Fri, 13 Sep 2019 09:14:07 -0400 Received: from localhost (unknown [104.132.45.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7AFCD20CC7; Fri, 13 Sep 2019 13:14:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380447; bh=mUBQxfQ32UvOlvNiMiNAHQHwA17r2wn3WVj5j3Oj+fg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jQmuBU1IUoNUbVyyiWfR3LnFs6lwZT2+L0PQNiHXkSIfHzJPKy1UGIYFFDLuFSyoK 3C1dSZWPbfmYEoaYKoVpJf1QTlwBQI1kvf7JOnv1ivytQnkKda9Xm3bngVmRb5Qwnv 4N2ok4TupEgzJR8TMZ/MVfNBHi4TRmq5mY8h9veY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Kuznetsov , Paolo Bonzini , Sasha Levin Subject: [PATCH 4.19 044/190] x86/kvm/lapic: preserve gfn_to_hva_cache len on cache reinit Date: Fri, 13 Sep 2019 14:04:59 +0100 Message-Id: <20190913130603.285535110@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190913130559.669563815@linuxfoundation.org> References: <20190913130559.669563815@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit a7c42bb6da6b1b54b2e7bd567636d72d87b10a79 ] vcpu->arch.pv_eoi is accessible through both HV_X64_MSR_VP_ASSIST_PAGE and MSR_KVM_PV_EOI_EN so on migration userspace may try to restore them in any order. Values match, however, kvm_lapic_enable_pv_eoi() uses different length: for Hyper-V case it's the whole struct hv_vp_assist_page, for KVM native case it is 8. In case we restore KVM-native MSR last cache will be reinitialized with len=8 so trying to access VP assist page beyond 8 bytes with kvm_read_guest_cached() will fail. Check if we re-initializing cache for the same address and preserve length in case it was greater. Signed-off-by: Vitaly Kuznetsov Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/x86/kvm/lapic.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 5427fd0aa97e1..262e49301cae6 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2636,14 +2636,22 @@ int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data) int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len) { u64 addr = data & ~KVM_MSR_ENABLED; + struct gfn_to_hva_cache *ghc = &vcpu->arch.pv_eoi.data; + unsigned long new_len; + if (!IS_ALIGNED(addr, 4)) return 1; vcpu->arch.pv_eoi.msr_val = data; if (!pv_eoi_enabled(vcpu)) return 0; - return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data, - addr, len); + + if (addr == ghc->gpa && len <= ghc->len) + new_len = ghc->len; + else + new_len = len; + + return kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, addr, new_len); } void kvm_apic_accept_events(struct kvm_vcpu *vcpu) -- 2.20.1