From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f200.google.com (mail-pg1-f200.google.com [209.85.215.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60B5A3B5318 for ; Wed, 26 Aug 2026 23:39:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787787564; cv=none; b=i1sKxmXdQh+Mnt0goSLNpYfgiV0DrwEVnyeG8sSY4uM2TSt8hhHK2ZNpVGCErnt6lER/kwNkz8XzeoI5dBzBOjzWoEt8yB4smI2XjHQGmr68eVRCXpkpjFlW/eVY4TzKr+NkvBK6qK//MVVRDddZiR20a73/VzCpFb8KPFuLP4I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787787564; c=relaxed/simple; bh=8Kw3Nj7xOGrbmUBSV/kVU/ochnXj0oWLrOcYJzQlq9k=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=coyDhG5H4SoWyIed85o1m22+WEe1C8Sruka89l137PFZWdOw+XC/qDOtNoHKtx6rR6GDvPBzdRH8s4l3D0gwppvpaz1oJYKm/7d9BMhOUDmFtfEI3eeIOQpbyc9w50qU9tyuYNKfW9z9E/HwTg1b75qlSteB7NHq6TqRghfbl4E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=GGbRjvei; arc=none smtp.client-ip=209.85.215.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="GGbRjvei" Received: by mail-pg1-f200.google.com with SMTP id 41be03b00d2f7-cc1b8088202so114413a12.3 for ; Wed, 26 Aug 2026 16:39:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1787787562; x=1788392362; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:reply-to:from:to:cc:subject:date:message-id :reply-to:content-type; bh=6KDDUNP2gAbt/e9olovJkhStLhLbdjWDJkc7h/s+5jY=; b=GGbRjveikoNGetF7QrLF+NAAKA3sL6KQFZCt7BQs5Kp61lUGryzyV9iOcfrwBDkFB1 RUOoT0Vz6a0ayrzVbqjkzoHQUaOWHhuZJqBM4jtOpUP4fLdvkTafictHuxZTplsG8PHw la4utzs0JucFNq4THvGkXzRDta7alFqF6Dk5sN8eb/NbZdurNvZdGhZRKaEH+BHUlEjs OWbn3E4WRvPt5R1qL3pmrMemu0EXUp6TmC6UF1O9qQc+vIIeEs/H7tRSM8YtcPGqRXB1 zV12F4AMqSOkfpCsAlDf904l9xoTItWZXAesYtPLaxeAJyWflDYSQlzudvqUOv4r9Dk3 s9yg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787787562; x=1788392362; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:reply-to:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to:content-type; bh=6KDDUNP2gAbt/e9olovJkhStLhLbdjWDJkc7h/s+5jY=; b=DbpSc3tp4BSUSDiXntLjZB/V6aElMyhTgDONryHh+rukbTq4LA6A9MycffZy+8I6R+ O6DrR4KPgEdYv8jQe2cNSu9AmqE3o4WgllNYeJW9kWoNui6AKF5qO8ZGvq6t372PbYJX v2BQbbxBXeCtMJ8ZbhGjKDdfIVtj+Rle7fQQz3ezdcL7R8y7MMVWSLFaqxfgyscFH2ND JYVR69xtHS+cb0KSBg4UQN1ngFxVYD29xpJDHQItkJ6gw6ZxJ73wLO1MCoz4SK04ShTn QIsHerOeGw3VO241I9d3fKTxnY64wvTWeb/fs3awXGxn/ll7Et2Rfu7d0rWqRWXS5uYI lZqA== X-Gm-Message-State: AFuF++khIOXtr45iC3eKjeOGEkcAxeQdg2b52CasYLiXT4rjThGhVdpz /0VBWY2WIB0wu3kHHVsUizcrMlT/AnpLyWcaS/mO/2thRAqBRv1yTW44zI1omsRIpvviKUug8j/ G4XD80w== X-Received: from pga9.prod.google.com ([2002:a05:6a02:4f89:b0:cc1:be9e:35ed]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a21:8986:b0:3d0:868d:8ccb with SMTP id adf61e73a8af0-3d0868d974amr10614945637.13.1787787561472; Wed, 26 Aug 2026 16:39:21 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 26 Aug 2026 16:39:07 -0700 In-Reply-To: <20260826233919.998904-1-seanjc@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260826233919.998904-1-seanjc@google.com> X-Mailer: git-send-email 2.55.0.887.g758fc8c411-goog Message-ID: <20260826233919.998904-2-seanjc@google.com> Subject: [PATCH v3 01/13] KVM: nVMX: Make VMPTRLD result in #UD when eVMCS is used From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, f734222792@gmail.com, Vitaly Kuznetsov , Sashiko Bot , Yosry Ahmed Content-Type: text/plain; charset="UTF-8" From: Vitaly Kuznetsov VMPTRLD with active eVMCS is already forbidden, however, returning 1 without skipping the instruction or queuing an exception will likely result in L1 getting stuck. Genuine Hyper-V seems to inject #UD under similar circumstances, mimic the behavior in KVM. Reported-by: f734222792@gmail.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=221841 Suggested-by: Sean Christopherson Signed-off-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/nested.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 151873407abd..ad3726fd4fda 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5897,6 +5897,12 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu) if (!nested_vmx_check_permission(vcpu)) return 1; + /* Forbid normal VMPTRLD if Enlightened version was used */ + if (nested_vmx_is_evmptr12_valid(vmx)) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } + if (nested_vmx_get_vmptr(vcpu, &vmptr, &r)) return r; @@ -5906,10 +5912,6 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu) if (vmptr == vmx->nested.vmxon_ptr) return nested_vmx_fail(vcpu, VMXERR_VMPTRLD_VMXON_POINTER); - /* Forbid normal VMPTRLD if Enlightened version was used */ - if (nested_vmx_is_evmptr12_valid(vmx)) - return 1; - if (vmx->nested.current_vmptr != vmptr) { struct gfn_to_hva_cache *ghc = &vmx->nested.vmcs12_cache; struct vmcs_hdr hdr; -- 2.55.0.887.g758fc8c411-goog