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 4ABCBC761A6 for ; Tue, 28 Mar 2023 04:38:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231978AbjC1Ein (ORCPT ); Tue, 28 Mar 2023 00:38:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231359AbjC1Eik (ORCPT ); Tue, 28 Mar 2023 00:38:40 -0400 Received: from mail-pj1-x1049.google.com (mail-pj1-x1049.google.com [IPv6:2607:f8b0:4864:20::1049]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3FADD1FFB for ; Mon, 27 Mar 2023 21:38:14 -0700 (PDT) Received: by mail-pj1-x1049.google.com with SMTP id b1-20020a17090a8c8100b002400db03706so2890424pjo.0 for ; Mon, 27 Mar 2023 21:38:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1679978294; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=rcAqgQ8BH2Pd6M4X5nC8yYas5XPVcEcHPdn5I8yTc5c=; b=F0y+ZlDZv9wReZiTDaK8D2Y9QzR6ohdjctRhdfVzmHxpj/4gFzrKKuHU65h5oumTdA hrxu4FVimICN0L3xUlSz69j8BsPIvHAbLBY8/VuRKrnlge0Vpo7X65mJhfUPF8jYeezg a4mrftgrNyPCrWsWXjF3f6KoFxkan+BJUxt38tE3gzIVRYU/aG8ssHFxvcWDi33R9k72 CkW1J94yEqUTAiRR8rlNlLtwPatPYJ07NvR2PmrofUDaLk+c6WtoaPXy5vBODi+K5Z/g DnthRq7G5PJvL/FTSF/4pnBcbfUc8K80FgH09Lob97afCVDMyUIqyfbfMc/sEvK2H5WM J1Ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679978294; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=rcAqgQ8BH2Pd6M4X5nC8yYas5XPVcEcHPdn5I8yTc5c=; b=DUg/6PDnjsvkAwujQGSyW/8g+Jx4AKLJL/aAjOVNI3ZoslWJn04Bz01rgDgcMfbMSb 6Y+bbN2frotU6FE/RpI0iuaIiJzWSFxJy09P+OOlE52GXTt4Aqi7M4MS+S0uQ1271FQd CXofuFhz2FXH8+BEloeJDLU/fW81s00nC7H4ECzUDl3m0A6WEFKLJff0PuG1rqUeaIf7 IGuvP4IFI2ih6/eTkMdmhSXxQ2ENdTRQ4Xyj+x5dQIjAoCckjhNlL8QniOV/CHKYCOo8 Q0QQVHdmS/1/GJSEmtHHG4RtUvrC+U+D6fIiiUWjoqKTU/ssPX3MKZ8tt2RnTkmrOAER lzkA== X-Gm-Message-State: AAQBX9eECCYzT/IhnCTlFh3g3Of03CJT1nxqF3KxUXQmpqMKHqcVcg1E yD1a4AmOihzbtgBfrjn9knm5re06kXo= X-Google-Smtp-Source: AKy350ZBV7I8ZBSrQ9pzx5uhdonFvp2L4ZDqEPY8dbkJruv2l0Ti8RKraySA1RqdgUvobnP7uUGSs9BFBxo= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:90a:5141:b0:23d:50d0:4ba4 with SMTP id k1-20020a17090a514100b0023d50d04ba4mr4324480pjm.3.1679978293792; Mon, 27 Mar 2023 21:38:13 -0700 (PDT) Date: Tue, 28 Mar 2023 04:38:12 +0000 In-Reply-To: Mime-Version: 1.0 References: <20230310125718.1442088-1-robert.hu@intel.com> <20230310125718.1442088-4-robert.hu@intel.com> Message-ID: Subject: Re: [PATCH 3/3] KVM: VMX: Use the canonical interface to read CR4.UMIP bit From: Sean Christopherson To: Robert Hoo Cc: Robert Hoo , pbonzini@redhat.com, kvm@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, Mar 11, 2023, Robert Hoo wrote: > Sean Christopherson =E4=BA=8E2023=E5=B9=B43=E6=9C=881= 1=E6=97=A5=E5=91=A8=E5=85=AD 00:27=E5=86=99=E9=81=93=EF=BC=9A > > Practically speaking, UMIP _can't_ be guest owned without breaking UMIP > emulation. >=20 > Agree. > Can we expect that in the future (not near future) that emulating UMIP > isn't needed at all? I mean, when all x86 CPUs on the market have UMIP in= native. Heh, define "all x86s on the market". UMIP didn't come along until Broadwe= ll, and we still get bug reports for Core2. It's going to be a long, long time bef= ore KVM can require UMIP support on Intel CPUs.