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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E599C433F5 for ; Mon, 7 Mar 2022 09:12:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236258AbiCGJNk (ORCPT ); Mon, 7 Mar 2022 04:13:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234885AbiCGJNi (ORCPT ); Mon, 7 Mar 2022 04:13:38 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id AFC4B27B2E for ; Mon, 7 Mar 2022 01:12:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646644363; 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=c+/Hjl0zyOOuFnsu7B/cwfXdvV4IHIHkTUvIXxRfjIc=; b=UMlYwrMhteGPnCOiHjFTSZEczzZIDz/6/gDBzG8GAKVbg6O7RmXSB+aL8x95875wXscXHz EYjWYvqIuDV91L0PnpoBK48C3nsLCGAR2ftgzgtYWEkuhnA02biuJqjKCgMIt5+tXDz8Bp K0unBOYVT1BicmpSBjWmC/TgC+uRdyU= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-73--pDVN4uGO-m3a3e9bw-5HQ-1; Mon, 07 Mar 2022 04:12:42 -0500 X-MC-Unique: -pDVN4uGO-m3a3e9bw-5HQ-1 Received: by mail-wm1-f70.google.com with SMTP id d8-20020a05600c34c800b0037e3cd6225eso5029614wmq.6 for ; Mon, 07 Mar 2022 01:12:42 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=c+/Hjl0zyOOuFnsu7B/cwfXdvV4IHIHkTUvIXxRfjIc=; b=j/EDCZJvkUKlF1rhKQDxxxi1gQIHIoQL/9HlGTM+cWBaUdT61TRveu1TCJAV8dEDhi rTDU8Cv0wOFy8x+mml1tvu/tA50lFw1mDdR1DeeFAArK5fKAWDFB4Nvj2M+nrrpLrUHf x3BGufR4gZUKFuz/WHfoJc3+sA8j6l/ULPGFFI+ob9ZCHyMVV9OsxIu2oQ2ov7EMIkHf mDA9ZtFI+aFBaOlM8dsZ1gNo7NYEuYrhsi6WzrKGLGGv1ZteXFoWSy8tDBkV+cFBHJgY CqQxhrDHCn6YFXXap+X3HqCauNgANrpM3E/Xpi/W3qibxLi4Ee6PaDALZm/0ZKilOokl ZTeA== X-Gm-Message-State: AOAM533gOwneXgJ5E4iOmEuwzHFnaxNmGBmGDK+B4Q00CkAUVFiIeBKe 2+ptt5ZWK+gqP01mPWLnlUtJBO4F0zZTvmcJelVjbpH1zN0oiFNoc8k0jMtZG1Jyt3Rl9TJDL+u NLs5b5hk7MUXg X-Received: by 2002:adf:e3d2:0:b0:1f1:d9b1:b5a8 with SMTP id k18-20020adfe3d2000000b001f1d9b1b5a8mr7341505wrm.499.1646644361533; Mon, 07 Mar 2022 01:12:41 -0800 (PST) X-Google-Smtp-Source: ABdhPJzf0ro+8gzIGF2cFevC9Cgf0kiVGSiBHipMijsey+1LsFqyQ1POBUgw9AxvN+ydDPjsSZ36Gw== X-Received: by 2002:adf:e3d2:0:b0:1f1:d9b1:b5a8 with SMTP id k18-20020adfe3d2000000b001f1d9b1b5a8mr7341490wrm.499.1646644361296; Mon, 07 Mar 2022 01:12:41 -0800 (PST) Received: from fedora (nat-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id n2-20020a05600c3b8200b00389a4ccd878sm3800807wms.0.2022.03.07.01.12.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Mar 2022 01:12:40 -0800 (PST) From: Vitaly Kuznetsov To: Li RongQing Cc: pbonzini@redhat.com, seanjc@google.com, jmattson@google.com, x86@kernel.org, kvm@vger.kernel.org, lirongqing@baidu.com Subject: Re: [PATCH][resend] KVM: x86: check steal time address when enable steal time In-Reply-To: <1646641011-55068-1-git-send-email-lirongqing@baidu.com> References: <1646641011-55068-1-git-send-email-lirongqing@baidu.com> Date: Mon, 07 Mar 2022 10:12:39 +0100 Message-ID: <87sfru9ldk.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Li RongQing writes: > check steal time address when enable steal time, do not update > arch.st.msr_val if the address is invalid, and return in #GP > > this can avoid unnecessary write/read invalid memory when guest > is running > > Signed-off-by: Li RongQing > --- > arch/x86/kvm/x86.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index eb402966..3ed0949 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -3616,6 +3616,9 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > if (data & KVM_STEAL_RESERVED_MASK) > return 1; > > + if (!kvm_vcpu_gfn_to_memslot(vcpu, data >> PAGE_SHIFT)) > + return 1; > + What about we use stronger kvm_is_visible_gfn() instead? I didn't put much thought to what's going to happen if we put e.g. APIC access page addr to the MSR, let's just cut any possibility. > vcpu->arch.st.msr_val = data; > > if (!(data & KVM_MSR_ENABLED)) -- Vitaly