From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2DF0C432C2 for ; Tue, 24 Sep 2019 13:54:22 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B48FB20872 for ; Tue, 24 Sep 2019 13:54:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B48FB20872 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45942 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iClGm-00084H-UI for qemu-devel@archiver.kernel.org; Tue, 24 Sep 2019 09:54:20 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52565) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iCkCl-0003NT-GY for qemu-devel@nongnu.org; Tue, 24 Sep 2019 08:46:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iCkCj-0004yd-RY for qemu-devel@nongnu.org; Tue, 24 Sep 2019 08:46:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46692) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iCkCj-0004yI-IE for qemu-devel@nongnu.org; Tue, 24 Sep 2019 08:46:05 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C26E1307D970; Tue, 24 Sep 2019 12:46:04 +0000 (UTC) Received: from dritchie.redhat.com (unknown [10.33.36.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id 94A0160933; Tue, 24 Sep 2019 12:45:58 +0000 (UTC) From: Sergio Lopez To: qemu-devel@nongnu.org Subject: [PATCH v4 7/8] docs/microvm.txt: document the new microvm machine type Date: Tue, 24 Sep 2019 14:44:32 +0200 Message-Id: <20190924124433.96810-8-slp@redhat.com> In-Reply-To: <20190924124433.96810-1-slp@redhat.com> References: <20190924124433.96810-1-slp@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Tue, 24 Sep 2019 12:46:04 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sergio Lopez , ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, lersek@redhat.com, mtosatti@redhat.com, kraxel@redhat.com, pbonzini@redhat.com, imammedo@redhat.com, philmd@redhat.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Document the new microvm machine type. Signed-off-by: Sergio Lopez --- docs/microvm.txt | 78 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 docs/microvm.txt diff --git a/docs/microvm.txt b/docs/microvm.txt new file mode 100644 index 0000000000..0241226b2a --- /dev/null +++ b/docs/microvm.txt @@ -0,0 +1,78 @@ +Microvm is a machine type inspired by both NEMU and Firecracker, and +constructed after the machine model implemented by the latter. + +It's main purpose is providing users a minimalist machine type free +from the burden of legacy compatibility, serving as a stepping stone +for future projects aiming at improving boot times, reducing the +attack surface and slimming down QEMU's footprint. + +The microvm machine type supports the following devices: + + - ISA bus + - i8259 PIC + - LAPIC (implicit if using KVM) + - IOAPIC (defaults to kernel_irqchip_split =3D true) + - i8254 PIT + - MC146818 RTC (optional) + - kvmclock (if using KVM) + - fw_cfg + - One ISA serial port (optional) + - Up to eight virtio-mmio devices (configured by the user) + +It supports the following machine-specific options: + +microvm.option-roms=3Dbool (Set off to disable loading option ROMs) +microvm.isa-serial=3Dbool (Set off to disable the instantiation an ISA s= erial port) +microvm.rtc=3Dbool (Set off to disable the instantiation of an MC146818 = RTC) +microvm.kernel-cmdline=3Dbool (Set off to disable adding virtio-mmio dev= ices to the kernel cmdline) + +By default, microvm uses qboot as its BIOS, to obtain better boot +times, but it's also compatible with SeaBIOS. + +As no current FW is able to boot from a block device using virtio-mmio +as its transport, a microvm-based VM needs to be run using a host-side +kernel and, optionally, an initrd image. + +This is an example of instantiating a microvm VM with a virtio-mmio +based console: + +qemu-system-x86_64 -M microvm + -enable-kvm -cpu host -m 512m -smp 2 \ + -kernel vmlinux -append "console=3Dhvc0 root=3D/dev/vda" \ + -nodefaults -no-user-config -nographic \ + -chardev stdio,id=3Dvirtiocon0,server \ + -device virtio-serial-device \ + -device virtconsole,chardev=3Dvirtiocon0 \ + -drive id=3Dtest,file=3Dtest.img,format=3Draw,if=3Dnone \ + -device virtio-blk-device,drive=3Dtest \ + -netdev tap,id=3Dtap0,script=3Dno,downscript=3Dno \ + -device virtio-net-device,netdev=3Dtap0 + +This is another example, this time using an ISA serial port, useful +for debugging purposes: + +qemu-system-x86_64 -M microvm \ + -enable-kvm -cpu host -m 512m -smp 2 \ + -kernel vmlinux -append "earlyprintk=3DttyS0 console=3DttyS0 root=3D/de= v/vda" \ + -nodefaults -no-user-config -nographic \ + -serial stdio \ + -drive id=3Dtest,file=3Dtest.img,format=3Draw,if=3Dnone \ + -device virtio-blk-device,drive=3Dtest \ + -netdev tap,id=3Dtap0,script=3Dno,downscript=3Dno \ + -device virtio-net-device,netdev=3Dtap0 + +Finally, in this example a microvm VM is instantiated without RTC, +without an ISA serial port and without loading the option ROMs, +obtaining the smallest configuration: + +qemu-system-x86_64 -M microvm,rtc=3Doff,isa-serial=3Doff,option-roms=3Do= ff \ + -enable-kvm -cpu host -m 512m -smp 2 \ + -kernel vmlinux -append "console=3Dhvc0 root=3D/dev/vda" \ + -nodefaults -no-user-config -nographic \ + -chardev stdio,id=3Dvirtiocon0,server \ + -device virtio-serial-device \ + -device virtconsole,chardev=3Dvirtiocon0 \ + -drive id=3Dtest,file=3Dtest.img,format=3Draw,if=3Dnone \ + -device virtio-blk-device,drive=3Dtest \ + -netdev tap,id=3Dtap0,script=3Dno,downscript=3Dno \ + -device virtio-net-device,netdev=3Dtap0 --=20 2.21.0