From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 17 Mar 2015 22:09:23 -0300 From: Marcelo Tosatti To: Radim =?utf-8?B?S3LEjW3DocWZ?= Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini , Kashyap Chamarthy , stable@vger.kernel.org Subject: Re: [PATCH RESEND] KVM: nVMX: mask unrestricted_guest if disabled on L0 Message-ID: <20150318010923.GA13570@amt.cnet> References: <1426597352-4115-1-git-send-email-rkrcmar@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1426597352-4115-1-git-send-email-rkrcmar@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Tue, Mar 17, 2015 at 02:02:32PM +0100, Radim Krčmář wrote: > If EPT was enabled, unrestricted_guest was allowed in L1 regardless of > L0. L1 triple faulted when running L2 guest that required emulation. > > Another side effect was 'WARN_ON_ONCE(vmx->nested.nested_run_pending)' > in L0's dmesg: > WARNING: CPU: 0 PID: 0 at arch/x86/kvm/vmx.c:9190 nested_vmx_vmexit+0x96e/0xb00 [kvm_intel] () > > Prevent this scenario by masking SECONDARY_EXEC_UNRESTRICTED_GUEST when > the host doesn't have it enabled. > > Fixes: 78051e3b7e35 ("KVM: nVMX: Disable unrestricted mode if ept=0") > Cc: stable@vger.kernel.org > Tested-By: Kashyap Chamarthy > Signed-off-by: Radim Krčmář > --- > The resend Cc'd stable, as recommended by Bandan, and added Tested-by. Applied to master, thanks.