Stefano Garzarella writes: > On Mon, Jul 01, 2019 at 04:47:05PM +0200, Sergio Lopez wrote: >> 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 KVM-only machine type with fast >> boot times, minimal attack surface (measured as the number of IO ports >> and MMIO regions exposed to the Guest) and small footprint (specially >> when combined with the ongoing QEMU modularization effort). >> >> Normally, other than the device support provided by KVM itself, >> microvm only supports virtio-mmio devices. Microvm also includes a >> legacy mode, which adds an ISA bus with a 16550A serial port, useful >> for being able to see the early boot kernel messages. >> >> Microvm only supports booting PVH-enabled Linux ELF images. Booting >> other PVH-enabled kernels may be possible, but due to the lack of ACPI >> and firmware, we're relying on the command line for specifying the >> location of the virtio-mmio transports. If there's an interest on >> using this machine type with other kernels, we'll try to find some >> kind of middle ground solution. >> >> Signed-off-by: Sergio Lopez >> --- >> default-configs/i386-softmmu.mak | 1 + >> hw/i386/Kconfig | 4 + >> hw/i386/Makefile.objs | 1 + >> hw/i386/microvm.c | 500 +++++++++++++++++++++++++++++++ >> include/hw/i386/microvm.h | 77 +++++ >> 5 files changed, 583 insertions(+) >> create mode 100644 hw/i386/microvm.c >> create mode 100644 include/hw/i386/microvm.h >> >> diff --git a/default-configs/i386-softmmu.mak b/default-configs/i386-softmmu.mak >> index cd5ea391e8..338f07420f 100644 >> --- a/default-configs/i386-softmmu.mak >> +++ b/default-configs/i386-softmmu.mak >> @@ -26,3 +26,4 @@ CONFIG_ISAPC=y >> CONFIG_I440FX=y >> CONFIG_Q35=y >> CONFIG_ACPI_PCI=y >> +CONFIG_MICROVM=y >> diff --git a/hw/i386/Kconfig b/hw/i386/Kconfig >> index 9817888216..94c565d8db 100644 >> --- a/hw/i386/Kconfig >> +++ b/hw/i386/Kconfig >> @@ -87,6 +87,10 @@ config Q35 >> select VMMOUSE >> select FW_CFG_DMA >> >> +config MICROVM >> + bool >> + select VIRTIO_MMIO >> + >> config VTD >> bool >> >> diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs >> index c5f20bbd72..7bffca413e 100644 >> --- a/hw/i386/Makefile.objs >> +++ b/hw/i386/Makefile.objs >> @@ -4,6 +4,7 @@ obj-y += pvh.o >> obj-y += pc.o >> obj-$(CONFIG_I440FX) += pc_piix.o >> obj-$(CONFIG_Q35) += pc_q35.o >> +obj-$(CONFIG_MICROVM) += mptable.o microvm.o >> obj-y += fw_cfg.o pc_sysfw.o >> obj-y += x86-iommu.o >> obj-$(CONFIG_VTD) += intel_iommu.o >> diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c >> new file mode 100644 >> index 0000000000..8b5efe9e45 >> --- /dev/null >> +++ b/hw/i386/microvm.c >> @@ -0,0 +1,500 @@ >> +/* >> + * Copyright (c) 2018 Intel Corporation >> + * Copyright (c) 2019 Red Hat, Inc. >> + * >> + * This program is free software; you can redistribute it and/or modify it >> + * under the terms and conditions of the GNU General Public License, >> + * version 2 or later, as published by the Free Software Foundation. >> + * >> + * This program is distributed in the hope it will be useful, but WITHOUT >> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or >> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for >> + * more details. >> + * >> + * You should have received a copy of the GNU General Public License along with >> + * this program. If not, see . >> + */ >> + >> +#include "qemu/osdep.h" >> +#include "qemu/error-report.h" >> +#include "qemu/cutils.h" >> +#include "qapi/error.h" >> +#include "qapi/visitor.h" >> +#include "sysemu/sysemu.h" >> +#include "sysemu/cpus.h" >> +#include "sysemu/numa.h" >> + >> +#include "hw/loader.h" >> +#include "hw/nmi.h" >> +#include "hw/kvm/clock.h" >> +#include "hw/i386/microvm.h" >> +#include "hw/i386/pc.h" >> +#include "target/i386/cpu.h" >> +#include "hw/timer/i8254.h" >> +#include "hw/char/serial.h" >> +#include "hw/i386/topology.h" >> +#include "hw/virtio/virtio-mmio.h" >> +#include "hw/i386/mptable.h" >> + >> +#include "cpu.h" >> +#include "elf.h" >> +#include "pvh.h" >> +#include "kvm_i386.h" >> +#include "hw/xen/start_info.h" >> + >> +static void microvm_gsi_handler(void *opaque, int n, int level) >> +{ >> + qemu_irq *ioapic_irq = opaque; >> + >> + qemu_set_irq(ioapic_irq[n], level); >> +} >> + >> +static void microvm_legacy_init(MicrovmMachineState *mms) >> +{ >> + ISABus *isa_bus; >> + GSIState *gsi_state; >> + qemu_irq *i8259; >> + int i; >> + >> + assert(kvm_irqchip_in_kernel()); >> + gsi_state = g_malloc0(sizeof(*gsi_state)); >> + mms->gsi = qemu_allocate_irqs(gsi_handler, gsi_state, GSI_NUM_PINS); >> + >> + isa_bus = isa_bus_new(NULL, get_system_memory(), get_system_io(), >> + &error_abort); >> + isa_bus_irqs(isa_bus, mms->gsi); >> + >> + assert(kvm_pic_in_kernel()); >> + i8259 = kvm_i8259_init(isa_bus); >> + >> + for (i = 0; i < ISA_NUM_IRQS; i++) { >> + gsi_state->i8259_irq[i] = i8259[i]; >> + } >> + >> + kvm_pit_init(isa_bus, 0x40); >> + >> + for (i = 0; i < VIRTIO_NUM_TRANSPORTS; i++) { >> + int nirq = VIRTIO_IRQ_BASE + i; >> + ISADevice *isadev = isa_create(isa_bus, TYPE_ISA_SERIAL); >> + qemu_irq mmio_irq; >> + >> + isa_init_irq(isadev, &mmio_irq, nirq); >> + sysbus_create_simple("virtio-mmio", >> + VIRTIO_MMIO_BASE + i * 512, >> + mms->gsi[VIRTIO_IRQ_BASE + i]); >> + } >> + >> + g_free(i8259); >> + >> + serial_hds_isa_init(isa_bus, 0, 1); >> +} >> + >> +static void microvm_ioapic_init(MicrovmMachineState *mms) >> +{ >> + qemu_irq *ioapic_irq; >> + DeviceState *ioapic_dev; >> + SysBusDevice *d; >> + int i; >> + >> + assert(kvm_irqchip_in_kernel()); >> + ioapic_irq = g_new0(qemu_irq, IOAPIC_NUM_PINS); >> + kvm_pc_setup_irq_routing(true); >> + >> + assert(kvm_ioapic_in_kernel()); >> + ioapic_dev = qdev_create(NULL, "kvm-ioapic"); >> + >> + object_property_add_child(qdev_get_machine(), >> + "ioapic", OBJECT(ioapic_dev), NULL); >> + >> + qdev_init_nofail(ioapic_dev); >> + d = SYS_BUS_DEVICE(ioapic_dev); >> + sysbus_mmio_map(d, 0, IO_APIC_DEFAULT_ADDRESS); >> + >> + for (i = 0; i < IOAPIC_NUM_PINS; i++) { >> + ioapic_irq[i] = qdev_get_gpio_in(ioapic_dev, i); >> + } >> + >> + mms->gsi = qemu_allocate_irqs(microvm_gsi_handler, >> + ioapic_irq, IOAPIC_NUM_PINS); >> + >> + for (i = 0; i < VIRTIO_NUM_TRANSPORTS; i++) { >> + sysbus_create_simple("virtio-mmio", >> + VIRTIO_MMIO_BASE + i * 512, >> + mms->gsi[VIRTIO_IRQ_BASE + i]); >> + } >> +} >> + >> +static void microvm_memory_init(MicrovmMachineState *mms) >> +{ >> + MachineState *machine = MACHINE(mms); >> + MemoryRegion *ram, *ram_below_4g, *ram_above_4g; >> + MemoryRegion *system_memory = get_system_memory(); >> + >> + if (machine->ram_size > MICROVM_MAX_BELOW_4G) { >> + mms->above_4g_mem_size = machine->ram_size - MICROVM_MAX_BELOW_4G; >> + mms->below_4g_mem_size = MICROVM_MAX_BELOW_4G; >> + } else { >> + mms->above_4g_mem_size = 0; >> + mms->below_4g_mem_size = machine->ram_size; >> + } >> + >> + ram = g_malloc(sizeof(*ram)); >> + memory_region_allocate_system_memory(ram, NULL, "microvm.ram", >> + machine->ram_size); >> + >> + ram_below_4g = g_malloc(sizeof(*ram_below_4g)); >> + memory_region_init_alias(ram_below_4g, NULL, "ram-below-4g", ram, >> + 0, mms->below_4g_mem_size); >> + memory_region_add_subregion(system_memory, 0, ram_below_4g); >> + >> + e820_add_entry(0, mms->below_4g_mem_size, E820_RAM); >> + >> + if (mms->above_4g_mem_size > 0) { >> + ram_above_4g = g_malloc(sizeof(*ram_above_4g)); >> + memory_region_init_alias(ram_above_4g, NULL, "ram-above-4g", ram, >> + mms->below_4g_mem_size, >> + mms->above_4g_mem_size); >> + memory_region_add_subregion(system_memory, 0x100000000ULL, >> + ram_above_4g); >> + e820_add_entry(0x100000000ULL, mms->above_4g_mem_size, E820_RAM); >> + } >> +} >> + >> +static void microvm_cpus_init(const char *typename, Error **errp) >> +{ >> + int i; >> + >> + for (i = 0; i < smp_cpus; i++) { >> + Object *cpu = NULL; >> + Error *local_err = NULL; >> + >> + cpu = object_new(typename); >> + >> + object_property_set_uint(cpu, i, "apic-id", &local_err); >> + object_property_set_bool(cpu, true, "realized", &local_err); >> + >> + object_unref(cpu); >> + error_propagate(errp, local_err); >> + } >> +} >> + >> +static void microvm_machine_state_init(MachineState *machine) >> +{ >> + MicrovmMachineState *mms = MICROVM_MACHINE(machine); >> + Error *local_err = NULL; >> + >> + if (machine->kernel_filename == NULL) { >> + error_report("missing kernel image file name, required by microvm"); >> + exit(1); >> + } > > Could it be useful to support initrd as well? > > I'm thinking a possibility to a microvm to use only the initrd without a > block device. I agree, thanks for the suggestion. I'll add support for it. Sergio. > In this case, Linux expects the initrd address and size in the first > element of the modlist in the 'struct hvm_start_info'. > > See pc-bios/optionrom/pvh_main.c > > Cheers, > Stefano