Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964844AbWJWN3G (ORCPT ); Mon, 23 Oct 2006 09:29:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964845AbWJWN3G (ORCPT ); Mon, 23 Oct 2006 09:29:06 -0400 Received: from mis011-1.exch011.intermedia.net ([64.78.21.128]:63376 "EHLO mis011-1.exch011.intermedia.net") by vger.kernel.org with ESMTP id S964844AbWJWN3E (ORCPT ); Mon, 23 Oct 2006 09:29:04 -0400 Message-ID: <453CC390.9080508@qumranet.com> Date: Mon, 23 Oct 2006 15:28:48 +0200 From: Avi Kivity User-Agent: Thunderbird 1.5.0.7 (X11/20060913) MIME-Version: 1.0 To: linux-kernel Subject: [PATCH 0/7] KVM: Kernel-based Virtual Machine (v2) Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 23 Oct 2006 13:28:53.0683 (UTC) FILETIME=[2F19D030:01C6F6A7] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2948 Lines: 76 Changes: - fixed a lockup on i386 with host memory >= 4GB - finer patch split to conform to vger limits - minor fixes - send through script to avoid mailer damage TODO: - drivers/ or arch/ ? - filesystem + syscalls or ioctl() ? I'll also reply to this mail with a sample userspace so people can see how it works. --- The following patchset adds a driver for Intel's hardware virtualization extensions to the x86 architecture. The driver adds a character device (/dev/kvm) that exposes the virtualization capabilities to userspace. Using this driver, a process can run a virtual machine (a "guest") in a fully virtualized PC containing its own virtual hard disks, network adapters, and display. Using this driver, one can start multiple virtual machines on a host. Each virtual machine is a process on the host; a virtual cpu is a thread in that process. kill(1), nice(1), top(1) work as expected. In effect, the driver adds a third execution mode to the existing two: we now have kernel mode, user mode, and guest mode. Guest mode has its own address space mapping guest physical memory (which is accessible to user mode by mmap()ing /dev/kvm). Guest mode has no access to any I/O devices; any such access is intercepted and directed to user mode for emulation. The driver supports i386 and x86_64 hosts and guests. All combinations are allowed except x86_64 guest on i386 host. For i386 guests and hosts, both pae and non-pae paging modes are supported. SMP hosts and UP guests are supported. At the moment only Intel hardware is supported, but AMD virtualization support is being worked on. Performance currently is non-stellar due to the naive implementation of the mmu virtualization, which throws away most of the shadow page table entries every context switch. We plan to address this in two ways: - cache shadow page tables across tlv flushes - wait until AMD and Intel release processors with nested page tables Currently a virtual desktop is responsive but consumes a lot of CPU. Under Windows I tried playing pinball and watching a few flash movies; with a recent CPU one can hardly feel the virtualization. Linux/X is slower, probably due to X being in a separate process. In addition to the driver, you need a slightly modified qemu to provide I/O device emulation and the BIOS. Caveats: - The Windows install currently bluescreens due to a problem with the virtual APIC. We are working on a fix. A temporary workaround is to use an existing image or install through qemu - Windows 64-bit does not work. That's also true for qemu, so it's probably a problem with the device model. -- error compiling committee.c: too many arguments to function - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/