From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH 6/8] KVM: SVM: Report emulated SVM features to userspace Date: Fri, 23 Apr 2010 16:21:19 +0200 Message-ID: <20100423142119.GF31537@amd.com> References: <1271932394-13968-1-git-send-email-joerg.roedel@amd.com> <1271932394-13968-7-git-send-email-joerg.roedel@amd.com> <60EF3E44-A41C-418E-9B03-8C245CA50699@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Avi Kivity , Marcelo Tosatti , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, stable@kernel.org To: Alexander Graf Return-path: Content-Disposition: inline In-Reply-To: <60EF3E44-A41C-418E-9B03-8C245CA50699@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Fri, Apr 23, 2010 at 03:55:15PM +0200, Alexander Graf wrote: > > On 22.04.2010, at 12:33, Joerg Roedel wrote: > > static void svm_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry) > > { > > + switch (func) { > > + case 0x8000000A: > > + entry->eax = 1; /* SVM revision 1 */ > > + entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper > > + ASID emulation to nested SVM */ > > I completely forgot what we do now. What do we do? It shouldn't be too > hard to keep a table around and just assign 8 host ASIDs to the guest. > If possible lazily, so we can just flush the whole thing when we run > out of entries. Currently we have no ASID emulation. We just assign a new asid at every vmrun/vmexit. But I have a rough idea of how we can emulate ASIDs for the L2 guest with an per-vcpu ASID cache. > It's basically the same as my VSID mapping on ppc64 actually. See > arch/powerpc/kvm/book3s_64_mmu_host.c and search for "slb". Thanks, will have a look there. > > + entry->ecx = 0; /* Reserved */ > > + entry->edx = 0; /* Do not support any additional features */ > > What about nnpt? Hasn't that been accepted yet? I am currently working on it. If all goes well I can submit a new version next week. Joerg