From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 2/2] KVM: SVM: Emulate next_rip svm feature Date: Wed, 28 Jul 2010 15:25:37 +0300 Message-ID: <4C5021C1.6030000@redhat.com> References: <1280247261-19115-1-git-send-email-joerg.roedel@amd.com> <1280247261-19115-3-git-send-email-joerg.roedel@amd.com> <4C4F2643.8080507@redhat.com> <20100728093708.GD26098@amd.com> <4C500636.1070708@redhat.com> <20100728112540.GE26098@amd.com> <4C5015B3.8010003@redhat.com> <20100728115133.GG26098@amd.com> <4C501B30.6020900@redhat.com> <20100728121822.GH26098@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" To: "Roedel, Joerg" Return-path: In-Reply-To: <20100728121822.GH26098@amd.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 07/28/2010 03:18 PM, Roedel, Joerg wrote: > > >> The guest (L2 in this case) is doomed since it execution cannot >> continue. But L1 and L0 are fine. The problem with L2 avoiding >> intercepts is that L2 can change control registers and take over L1. > Right too. We can not ignore it. The right fix is probably a check for > the instruction intercepts right after the decoder has run and before > the emulator ran. Should be easy - just like we have the Priv flag, add a bitfield to opcode_table that says which bit we need to check in the control area. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.