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=-10.1 required=3.0 tests=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 12B03C3A5A2 for ; Tue, 3 Sep 2019 16:39:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DFFF02339D for ; Tue, 3 Sep 2019 16:39:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567528757; bh=K9OcstgoEAF/+7QGbfId/spEmXyKk4gKH5hsBnfLJQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=A4hHhCe4YpvuIHbVoB9wHMUd4tO6/Hs8bsnhNnEL3G6+FuIvQDxbgrEqmCetIk+uu MmC8Qc+SyvEYIs5UwnnbJo8pFoNZyecv2ydkvpXcS0Z5PkrPcMsA6yma8B3IL1fSuO Je7gKbTUn/uyFjtppyjP9MpTDfuJly9qopfllOL0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730479AbfICQZt (ORCPT ); Tue, 3 Sep 2019 12:25:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:46098 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730465AbfICQZt (ORCPT ); Tue, 3 Sep 2019 12:25:49 -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 5F0A823774; Tue, 3 Sep 2019 16:25:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567527948; bh=K9OcstgoEAF/+7QGbfId/spEmXyKk4gKH5hsBnfLJQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wb+4hR4sFuf+r6j2E2nYalSeQDGRmNxDui5WmW61JC8N7XEql+adOYHsFvdJfHM5H 4uAC4K2yoNqU/okbPRr9+AQwzjEDEZPg7Rf+ZJOHJWePEisoUNWxRwrmevcNuScVtK hw9R4QHBcCiu8h4b+j818OEIbdf/LF98vdTI+ST4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vitaly Kuznetsov , Paolo Bonzini , Sasha Levin , kvm@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 015/167] x86/kvm/lapic: preserve gfn_to_hva_cache len on cache reinit Date: Tue, 3 Sep 2019 12:22:47 -0400 Message-Id: <20190903162519.7136-15-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190903162519.7136-1-sashal@kernel.org> References: <20190903162519.7136-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Vitaly Kuznetsov [ 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 ccf5a04de94c3..973a244081d34 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2631,14 +2631,22 @@ 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