qemu-patch-raspberry4/hw/i386/x86.c
Chenyi Qiang 035d1ef265 i386: Add ratelimit for bus locks acquired in guest
A bus lock is acquired through either split locked access to writeback
(WB) memory or any locked access to non-WB memory. It is typically >1000
cycles slower than an atomic operation within a cache and can also
disrupts performance on other cores.

Virtual Machines can exploit bus locks to degrade the performance of
system. To address this kind of performance DOS attack coming from the
VMs, bus lock VM exit is introduced in KVM and it can report the bus
locks detected in guest. If enabled in KVM, it would exit to the
userspace to let the user enforce throttling policies once bus locks
acquired in VMs.

The availability of bus lock VM exit can be detected through the
KVM_CAP_X86_BUS_LOCK_EXIT. The returned bitmap contains the potential
policies supported by KVM. The field KVM_BUS_LOCK_DETECTION_EXIT in
bitmap is the only supported strategy at present. It indicates that KVM
will exit to userspace to handle the bus locks.

This patch adds a ratelimit on the bus locks acquired in guest as a
mitigation policy.

Introduce a new field "bus_lock_ratelimit" to record the limited speed
of bus locks in the target VM. The user can specify it through the
"bus-lock-ratelimit" as a machine property. In current implementation,
the default value of the speed is 0 per second, which means no
restrictions on the bus locks.

As for ratelimit on detected bus locks, simply set the ratelimit
interval to 1s and restrict the quota of bus lock occurence to the value
of "bus_lock_ratelimit". A potential alternative is to introduce the
time slice as a property which can help the user achieve more precise
control.

The detail of bus lock VM exit can be found in spec:
https://software.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html

Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20210521043820.29678-1-chenyi.qiang@intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2021-06-17 14:11:06 -04:00

1348 lines
43 KiB
C

/*
* Copyright (c) 2003-2004 Fabrice Bellard
* Copyright (c) 2019 Red Hat, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "qemu/cutils.h"
#include "qemu/units.h"
#include "qemu-common.h"
#include "qemu/datadir.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qapi-visit-common.h"
#include "qapi/visitor.h"
#include "sysemu/qtest.h"
#include "sysemu/whpx.h"
#include "sysemu/numa.h"
#include "sysemu/replay.h"
#include "sysemu/sysemu.h"
#include "sysemu/cpu-timers.h"
#include "trace.h"
#include "hw/i386/x86.h"
#include "target/i386/cpu.h"
#include "hw/i386/topology.h"
#include "hw/i386/fw_cfg.h"
#include "hw/intc/i8259.h"
#include "hw/rtc/mc146818rtc.h"
#include "hw/acpi/cpu_hotplug.h"
#include "hw/irq.h"
#include "hw/nmi.h"
#include "hw/loader.h"
#include "multiboot.h"
#include "elf.h"
#include "standard-headers/asm-x86/bootparam.h"
#include CONFIG_DEVICES
#include "kvm/kvm_i386.h"
/* Physical Address of PVH entry point read from kernel ELF NOTE */
static size_t pvh_start_addr;
inline void init_topo_info(X86CPUTopoInfo *topo_info,
const X86MachineState *x86ms)
{
MachineState *ms = MACHINE(x86ms);
topo_info->dies_per_pkg = x86ms->smp_dies;
topo_info->cores_per_die = ms->smp.cores;
topo_info->threads_per_core = ms->smp.threads;
}
/*
* Calculates initial APIC ID for a specific CPU index
*
* Currently we need to be able to calculate the APIC ID from the CPU index
* alone (without requiring a CPU object), as the QEMU<->Seabios interfaces have
* no concept of "CPU index", and the NUMA tables on fw_cfg need the APIC ID of
* all CPUs up to max_cpus.
*/
uint32_t x86_cpu_apic_id_from_index(X86MachineState *x86ms,
unsigned int cpu_index)
{
X86MachineClass *x86mc = X86_MACHINE_GET_CLASS(x86ms);
X86CPUTopoInfo topo_info;
uint32_t correct_id;
static bool warned;
init_topo_info(&topo_info, x86ms);
correct_id = x86_apicid_from_cpu_idx(&topo_info, cpu_index);
if (x86mc->compat_apic_id_mode) {
if (cpu_index != correct_id && !warned && !qtest_enabled()) {
error_report("APIC IDs set in compatibility mode, "
"CPU topology won't match the configuration");
warned = true;
}
return cpu_index;
} else {
return correct_id;
}
}
void x86_cpu_new(X86MachineState *x86ms, int64_t apic_id, Error **errp)
{
Object *cpu = object_new(MACHINE(x86ms)->cpu_type);
if (!object_property_set_uint(cpu, "apic-id", apic_id, errp)) {
goto out;
}
qdev_realize(DEVICE(cpu), NULL, errp);
out:
object_unref(cpu);
}
void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
{
int i;
const CPUArchIdList *possible_cpus;
MachineState *ms = MACHINE(x86ms);
MachineClass *mc = MACHINE_GET_CLASS(x86ms);
x86_cpu_set_default_version(default_cpu_version);
/*
* Calculates the limit to CPU APIC ID values
*
* Limit for the APIC ID value, so that all
* CPU APIC IDs are < x86ms->apic_id_limit.
*
* This is used for FW_CFG_MAX_CPUS. See comments on fw_cfg_arch_create().
*/
x86ms->apic_id_limit = x86_cpu_apic_id_from_index(x86ms,
ms->smp.max_cpus - 1) + 1;
possible_cpus = mc->possible_cpu_arch_ids(ms);
for (i = 0; i < ms->smp.cpus; i++) {
x86_cpu_new(x86ms, possible_cpus->cpus[i].arch_id, &error_fatal);
}
}
void x86_rtc_set_cpus_count(ISADevice *rtc, uint16_t cpus_count)
{
if (cpus_count > 0xff) {
/*
* If the number of CPUs can't be represented in 8 bits, the
* BIOS must use "FW_CFG_NB_CPUS". Set RTC field to 0 just
* to make old BIOSes fail more predictably.
*/
rtc_set_memory(rtc, 0x5f, 0);
} else {
rtc_set_memory(rtc, 0x5f, cpus_count - 1);
}
}
static int x86_apic_cmp(const void *a, const void *b)
{
CPUArchId *apic_a = (CPUArchId *)a;
CPUArchId *apic_b = (CPUArchId *)b;
return apic_a->arch_id - apic_b->arch_id;
}
/*
* returns pointer to CPUArchId descriptor that matches CPU's apic_id
* in ms->possible_cpus->cpus, if ms->possible_cpus->cpus has no
* entry corresponding to CPU's apic_id returns NULL.
*/
CPUArchId *x86_find_cpu_slot(MachineState *ms, uint32_t id, int *idx)
{
CPUArchId apic_id, *found_cpu;
apic_id.arch_id = id;
found_cpu = bsearch(&apic_id, ms->possible_cpus->cpus,
ms->possible_cpus->len, sizeof(*ms->possible_cpus->cpus),
x86_apic_cmp);
if (found_cpu && idx) {
*idx = found_cpu - ms->possible_cpus->cpus;
}
return found_cpu;
}
void x86_cpu_plug(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
CPUArchId *found_cpu;
Error *local_err = NULL;
X86CPU *cpu = X86_CPU(dev);
X86MachineState *x86ms = X86_MACHINE(hotplug_dev);
if (x86ms->acpi_dev) {
hotplug_handler_plug(x86ms->acpi_dev, dev, &local_err);
if (local_err) {
goto out;
}
}
/* increment the number of CPUs */
x86ms->boot_cpus++;
if (x86ms->rtc) {
x86_rtc_set_cpus_count(x86ms->rtc, x86ms->boot_cpus);
}
if (x86ms->fw_cfg) {
fw_cfg_modify_i16(x86ms->fw_cfg, FW_CFG_NB_CPUS, x86ms->boot_cpus);
}
found_cpu = x86_find_cpu_slot(MACHINE(x86ms), cpu->apic_id, NULL);
found_cpu->cpu = OBJECT(dev);
out:
error_propagate(errp, local_err);
}
void x86_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
int idx = -1;
X86CPU *cpu = X86_CPU(dev);
X86MachineState *x86ms = X86_MACHINE(hotplug_dev);
if (!x86ms->acpi_dev) {
error_setg(errp, "CPU hot unplug not supported without ACPI");
return;
}
x86_find_cpu_slot(MACHINE(x86ms), cpu->apic_id, &idx);
assert(idx != -1);
if (idx == 0) {
error_setg(errp, "Boot CPU is unpluggable");
return;
}
hotplug_handler_unplug_request(x86ms->acpi_dev, dev,
errp);
}
void x86_cpu_unplug_cb(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
CPUArchId *found_cpu;
Error *local_err = NULL;
X86CPU *cpu = X86_CPU(dev);
X86MachineState *x86ms = X86_MACHINE(hotplug_dev);
hotplug_handler_unplug(x86ms->acpi_dev, dev, &local_err);
if (local_err) {
goto out;
}
found_cpu = x86_find_cpu_slot(MACHINE(x86ms), cpu->apic_id, NULL);
found_cpu->cpu = NULL;
qdev_unrealize(dev);
/* decrement the number of CPUs */
x86ms->boot_cpus--;
/* Update the number of CPUs in CMOS */
x86_rtc_set_cpus_count(x86ms->rtc, x86ms->boot_cpus);
fw_cfg_modify_i16(x86ms->fw_cfg, FW_CFG_NB_CPUS, x86ms->boot_cpus);
out:
error_propagate(errp, local_err);
}
void x86_cpu_pre_plug(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
int idx;
CPUState *cs;
CPUArchId *cpu_slot;
X86CPUTopoIDs topo_ids;
X86CPU *cpu = X86_CPU(dev);
CPUX86State *env = &cpu->env;
MachineState *ms = MACHINE(hotplug_dev);
X86MachineState *x86ms = X86_MACHINE(hotplug_dev);
unsigned int smp_cores = ms->smp.cores;
unsigned int smp_threads = ms->smp.threads;
X86CPUTopoInfo topo_info;
if (!object_dynamic_cast(OBJECT(cpu), ms->cpu_type)) {
error_setg(errp, "Invalid CPU type, expected cpu type: '%s'",
ms->cpu_type);
return;
}
if (x86ms->acpi_dev) {
Error *local_err = NULL;
hotplug_handler_pre_plug(HOTPLUG_HANDLER(x86ms->acpi_dev), dev,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
init_topo_info(&topo_info, x86ms);
env->nr_dies = x86ms->smp_dies;
/*
* If APIC ID is not set,
* set it based on socket/die/core/thread properties.
*/
if (cpu->apic_id == UNASSIGNED_APIC_ID) {
int max_socket = (ms->smp.max_cpus - 1) /
smp_threads / smp_cores / x86ms->smp_dies;
/*
* die-id was optional in QEMU 4.0 and older, so keep it optional
* if there's only one die per socket.
*/
if (cpu->die_id < 0 && x86ms->smp_dies == 1) {
cpu->die_id = 0;
}
if (cpu->socket_id < 0) {
error_setg(errp, "CPU socket-id is not set");
return;
} else if (cpu->socket_id > max_socket) {
error_setg(errp, "Invalid CPU socket-id: %u must be in range 0:%u",
cpu->socket_id, max_socket);
return;
}
if (cpu->die_id < 0) {
error_setg(errp, "CPU die-id is not set");
return;
} else if (cpu->die_id > x86ms->smp_dies - 1) {
error_setg(errp, "Invalid CPU die-id: %u must be in range 0:%u",
cpu->die_id, x86ms->smp_dies - 1);
return;
}
if (cpu->core_id < 0) {
error_setg(errp, "CPU core-id is not set");
return;
} else if (cpu->core_id > (smp_cores - 1)) {
error_setg(errp, "Invalid CPU core-id: %u must be in range 0:%u",
cpu->core_id, smp_cores - 1);
return;
}
if (cpu->thread_id < 0) {
error_setg(errp, "CPU thread-id is not set");
return;
} else if (cpu->thread_id > (smp_threads - 1)) {
error_setg(errp, "Invalid CPU thread-id: %u must be in range 0:%u",
cpu->thread_id, smp_threads - 1);
return;
}
topo_ids.pkg_id = cpu->socket_id;
topo_ids.die_id = cpu->die_id;
topo_ids.core_id = cpu->core_id;
topo_ids.smt_id = cpu->thread_id;
cpu->apic_id = x86_apicid_from_topo_ids(&topo_info, &topo_ids);
}
cpu_slot = x86_find_cpu_slot(MACHINE(x86ms), cpu->apic_id, &idx);
if (!cpu_slot) {
MachineState *ms = MACHINE(x86ms);
x86_topo_ids_from_apicid(cpu->apic_id, &topo_info, &topo_ids);
error_setg(errp,
"Invalid CPU [socket: %u, die: %u, core: %u, thread: %u] with"
" APIC ID %" PRIu32 ", valid index range 0:%d",
topo_ids.pkg_id, topo_ids.die_id, topo_ids.core_id, topo_ids.smt_id,
cpu->apic_id, ms->possible_cpus->len - 1);
return;
}
if (cpu_slot->cpu) {
error_setg(errp, "CPU[%d] with APIC ID %" PRIu32 " exists",
idx, cpu->apic_id);
return;
}
/* if 'address' properties socket-id/core-id/thread-id are not set, set them
* so that machine_query_hotpluggable_cpus would show correct values
*/
/* TODO: move socket_id/core_id/thread_id checks into x86_cpu_realizefn()
* once -smp refactoring is complete and there will be CPU private
* CPUState::nr_cores and CPUState::nr_threads fields instead of globals */
x86_topo_ids_from_apicid(cpu->apic_id, &topo_info, &topo_ids);
if (cpu->socket_id != -1 && cpu->socket_id != topo_ids.pkg_id) {
error_setg(errp, "property socket-id: %u doesn't match set apic-id:"
" 0x%x (socket-id: %u)", cpu->socket_id, cpu->apic_id,
topo_ids.pkg_id);
return;
}
cpu->socket_id = topo_ids.pkg_id;
if (cpu->die_id != -1 && cpu->die_id != topo_ids.die_id) {
error_setg(errp, "property die-id: %u doesn't match set apic-id:"
" 0x%x (die-id: %u)", cpu->die_id, cpu->apic_id, topo_ids.die_id);
return;
}
cpu->die_id = topo_ids.die_id;
if (cpu->core_id != -1 && cpu->core_id != topo_ids.core_id) {
error_setg(errp, "property core-id: %u doesn't match set apic-id:"
" 0x%x (core-id: %u)", cpu->core_id, cpu->apic_id,
topo_ids.core_id);
return;
}
cpu->core_id = topo_ids.core_id;
if (cpu->thread_id != -1 && cpu->thread_id != topo_ids.smt_id) {
error_setg(errp, "property thread-id: %u doesn't match set apic-id:"
" 0x%x (thread-id: %u)", cpu->thread_id, cpu->apic_id,
topo_ids.smt_id);
return;
}
cpu->thread_id = topo_ids.smt_id;
if (hyperv_feat_enabled(cpu, HYPERV_FEAT_VPINDEX) &&
!kvm_hv_vpindex_settable()) {
error_setg(errp, "kernel doesn't allow setting HyperV VP_INDEX");
return;
}
cs = CPU(cpu);
cs->cpu_index = idx;
numa_cpu_pre_plug(cpu_slot, dev, errp);
}
CpuInstanceProperties
x86_cpu_index_to_props(MachineState *ms, unsigned cpu_index)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
const CPUArchIdList *possible_cpus = mc->possible_cpu_arch_ids(ms);
assert(cpu_index < possible_cpus->len);
return possible_cpus->cpus[cpu_index].props;
}
int64_t x86_get_default_cpu_node_id(const MachineState *ms, int idx)
{
X86CPUTopoIDs topo_ids;
X86MachineState *x86ms = X86_MACHINE(ms);
X86CPUTopoInfo topo_info;
init_topo_info(&topo_info, x86ms);
assert(idx < ms->possible_cpus->len);
x86_topo_ids_from_apicid(ms->possible_cpus->cpus[idx].arch_id,
&topo_info, &topo_ids);
return topo_ids.pkg_id % ms->numa_state->num_nodes;
}
const CPUArchIdList *x86_possible_cpu_arch_ids(MachineState *ms)
{
X86MachineState *x86ms = X86_MACHINE(ms);
unsigned int max_cpus = ms->smp.max_cpus;
X86CPUTopoInfo topo_info;
int i;
if (ms->possible_cpus) {
/*
* make sure that max_cpus hasn't changed since the first use, i.e.
* -smp hasn't been parsed after it
*/
assert(ms->possible_cpus->len == max_cpus);
return ms->possible_cpus;
}
ms->possible_cpus = g_malloc0(sizeof(CPUArchIdList) +
sizeof(CPUArchId) * max_cpus);
ms->possible_cpus->len = max_cpus;
init_topo_info(&topo_info, x86ms);
for (i = 0; i < ms->possible_cpus->len; i++) {
X86CPUTopoIDs topo_ids;
ms->possible_cpus->cpus[i].type = ms->cpu_type;
ms->possible_cpus->cpus[i].vcpus_count = 1;
ms->possible_cpus->cpus[i].arch_id =
x86_cpu_apic_id_from_index(x86ms, i);
x86_topo_ids_from_apicid(ms->possible_cpus->cpus[i].arch_id,
&topo_info, &topo_ids);
ms->possible_cpus->cpus[i].props.has_socket_id = true;
ms->possible_cpus->cpus[i].props.socket_id = topo_ids.pkg_id;
if (x86ms->smp_dies > 1) {
ms->possible_cpus->cpus[i].props.has_die_id = true;
ms->possible_cpus->cpus[i].props.die_id = topo_ids.die_id;
}
ms->possible_cpus->cpus[i].props.has_core_id = true;
ms->possible_cpus->cpus[i].props.core_id = topo_ids.core_id;
ms->possible_cpus->cpus[i].props.has_thread_id = true;
ms->possible_cpus->cpus[i].props.thread_id = topo_ids.smt_id;
}
return ms->possible_cpus;
}
static void x86_nmi(NMIState *n, int cpu_index, Error **errp)
{
/* cpu index isn't used */
CPUState *cs;
CPU_FOREACH(cs) {
X86CPU *cpu = X86_CPU(cs);
if (!cpu->apic_state) {
cpu_interrupt(cs, CPU_INTERRUPT_NMI);
} else {
apic_deliver_nmi(cpu->apic_state);
}
}
}
static long get_file_size(FILE *f)
{
long where, size;
/* XXX: on Unix systems, using fstat() probably makes more sense */
where = ftell(f);
fseek(f, 0, SEEK_END);
size = ftell(f);
fseek(f, where, SEEK_SET);
return size;
}
/* TSC handling */
uint64_t cpu_get_tsc(CPUX86State *env)
{
return cpus_get_elapsed_ticks();
}
/* IRQ handling */
static void pic_irq_request(void *opaque, int irq, int level)
{
CPUState *cs = first_cpu;
X86CPU *cpu = X86_CPU(cs);
trace_x86_pic_interrupt(irq, level);
if (cpu->apic_state && !kvm_irqchip_in_kernel() &&
!whpx_apic_in_platform()) {
CPU_FOREACH(cs) {
cpu = X86_CPU(cs);
if (apic_accept_pic_intr(cpu->apic_state)) {
apic_deliver_pic_intr(cpu->apic_state, level);
}
}
} else {
if (level) {
cpu_interrupt(cs, CPU_INTERRUPT_HARD);
} else {
cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
}
}
}
qemu_irq x86_allocate_cpu_irq(void)
{
return qemu_allocate_irq(pic_irq_request, NULL, 0);
}
int cpu_get_pic_interrupt(CPUX86State *env)
{
X86CPU *cpu = env_archcpu(env);
int intno;
if (!kvm_irqchip_in_kernel() && !whpx_apic_in_platform()) {
intno = apic_get_interrupt(cpu->apic_state);
if (intno >= 0) {
return intno;
}
/* read the irq from the PIC */
if (!apic_accept_pic_intr(cpu->apic_state)) {
return -1;
}
}
intno = pic_read_irq(isa_pic);
return intno;
}
DeviceState *cpu_get_current_apic(void)
{
if (current_cpu) {
X86CPU *cpu = X86_CPU(current_cpu);
return cpu->apic_state;
} else {
return NULL;
}
}
void gsi_handler(void *opaque, int n, int level)
{
GSIState *s = opaque;
trace_x86_gsi_interrupt(n, level);
switch (n) {
case 0 ... ISA_NUM_IRQS - 1:
if (s->i8259_irq[n]) {
/* Under KVM, Kernel will forward to both PIC and IOAPIC */
qemu_set_irq(s->i8259_irq[n], level);
}
/* fall through */
case ISA_NUM_IRQS ... IOAPIC_NUM_PINS - 1:
qemu_set_irq(s->ioapic_irq[n], level);
break;
case IO_APIC_SECONDARY_IRQBASE
... IO_APIC_SECONDARY_IRQBASE + IOAPIC_NUM_PINS - 1:
qemu_set_irq(s->ioapic2_irq[n - IO_APIC_SECONDARY_IRQBASE], level);
break;
}
}
void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name)
{
DeviceState *dev;
SysBusDevice *d;
unsigned int i;
assert(parent_name);
if (kvm_ioapic_in_kernel()) {
dev = qdev_new(TYPE_KVM_IOAPIC);
} else {
dev = qdev_new(TYPE_IOAPIC);
}
object_property_add_child(object_resolve_path(parent_name, NULL),
"ioapic", OBJECT(dev));
d = SYS_BUS_DEVICE(dev);
sysbus_realize_and_unref(d, &error_fatal);
sysbus_mmio_map(d, 0, IO_APIC_DEFAULT_ADDRESS);
for (i = 0; i < IOAPIC_NUM_PINS; i++) {
gsi_state->ioapic_irq[i] = qdev_get_gpio_in(dev, i);
}
}
DeviceState *ioapic_init_secondary(GSIState *gsi_state)
{
DeviceState *dev;
SysBusDevice *d;
unsigned int i;
dev = qdev_new(TYPE_IOAPIC);
d = SYS_BUS_DEVICE(dev);
sysbus_realize_and_unref(d, &error_fatal);
sysbus_mmio_map(d, 0, IO_APIC_SECONDARY_ADDRESS);
for (i = 0; i < IOAPIC_NUM_PINS; i++) {
gsi_state->ioapic2_irq[i] = qdev_get_gpio_in(dev, i);
}
return dev;
}
struct setup_data {
uint64_t next;
uint32_t type;
uint32_t len;
uint8_t data[];
} __attribute__((packed));
/*
* The entry point into the kernel for PVH boot is different from
* the native entry point. The PVH entry is defined by the x86/HVM
* direct boot ABI and is available in an ELFNOTE in the kernel binary.
*
* This function is passed to load_elf() when it is called from
* load_elfboot() which then additionally checks for an ELF Note of
* type XEN_ELFNOTE_PHYS32_ENTRY and passes it to this function to
* parse the PVH entry address from the ELF Note.
*
* Due to trickery in elf_opts.h, load_elf() is actually available as
* load_elf32() or load_elf64() and this routine needs to be able
* to deal with being called as 32 or 64 bit.
*
* The address of the PVH entry point is saved to the 'pvh_start_addr'
* global variable. (although the entry point is 32-bit, the kernel
* binary can be either 32-bit or 64-bit).
*/
static uint64_t read_pvh_start_addr(void *arg1, void *arg2, bool is64)
{
size_t *elf_note_data_addr;
/* Check if ELF Note header passed in is valid */
if (arg1 == NULL) {
return 0;
}
if (is64) {
struct elf64_note *nhdr64 = (struct elf64_note *)arg1;
uint64_t nhdr_size64 = sizeof(struct elf64_note);
uint64_t phdr_align = *(uint64_t *)arg2;
uint64_t nhdr_namesz = nhdr64->n_namesz;
elf_note_data_addr =
((void *)nhdr64) + nhdr_size64 +
QEMU_ALIGN_UP(nhdr_namesz, phdr_align);
pvh_start_addr = *elf_note_data_addr;
} else {
struct elf32_note *nhdr32 = (struct elf32_note *)arg1;
uint32_t nhdr_size32 = sizeof(struct elf32_note);
uint32_t phdr_align = *(uint32_t *)arg2;
uint32_t nhdr_namesz = nhdr32->n_namesz;
elf_note_data_addr =
((void *)nhdr32) + nhdr_size32 +
QEMU_ALIGN_UP(nhdr_namesz, phdr_align);
pvh_start_addr = *(uint32_t *)elf_note_data_addr;
}
return pvh_start_addr;
}
static bool load_elfboot(const char *kernel_filename,
int kernel_file_size,
uint8_t *header,
size_t pvh_xen_start_addr,
FWCfgState *fw_cfg)
{
uint32_t flags = 0;
uint32_t mh_load_addr = 0;
uint32_t elf_kernel_size = 0;
uint64_t elf_entry;
uint64_t elf_low, elf_high;
int kernel_size;
if (ldl_p(header) != 0x464c457f) {
return false; /* no elfboot */
}
bool elf_is64 = header[EI_CLASS] == ELFCLASS64;
flags = elf_is64 ?
((Elf64_Ehdr *)header)->e_flags : ((Elf32_Ehdr *)header)->e_flags;
if (flags & 0x00010004) { /* LOAD_ELF_HEADER_HAS_ADDR */
error_report("elfboot unsupported flags = %x", flags);
exit(1);
}
uint64_t elf_note_type = XEN_ELFNOTE_PHYS32_ENTRY;
kernel_size = load_elf(kernel_filename, read_pvh_start_addr,
NULL, &elf_note_type, &elf_entry,
&elf_low, &elf_high, NULL, 0, I386_ELF_MACHINE,
0, 0);
if (kernel_size < 0) {
error_report("Error while loading elf kernel");
exit(1);
}
mh_load_addr = elf_low;
elf_kernel_size = elf_high - elf_low;
if (pvh_start_addr == 0) {
error_report("Error loading uncompressed kernel without PVH ELF Note");
exit(1);
}
fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ENTRY, pvh_start_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, mh_load_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, elf_kernel_size);
return true;
}
void x86_load_linux(X86MachineState *x86ms,
FWCfgState *fw_cfg,
int acpi_data_size,
bool pvh_enabled,
bool linuxboot_dma_enabled)
{
uint16_t protocol;
int setup_size, kernel_size, cmdline_size;
int dtb_size, setup_data_offset;
uint32_t initrd_max;
uint8_t header[8192], *setup, *kernel;
hwaddr real_addr, prot_addr, cmdline_addr, initrd_addr = 0;
FILE *f;
char *vmode;
MachineState *machine = MACHINE(x86ms);
struct setup_data *setup_data;
const char *kernel_filename = machine->kernel_filename;
const char *initrd_filename = machine->initrd_filename;
const char *dtb_filename = machine->dtb;
const char *kernel_cmdline = machine->kernel_cmdline;
/* Align to 16 bytes as a paranoia measure */
cmdline_size = (strlen(kernel_cmdline) + 16) & ~15;
/* load the kernel header */
f = fopen(kernel_filename, "rb");
if (!f) {
fprintf(stderr, "qemu: could not open kernel file '%s': %s\n",
kernel_filename, strerror(errno));
exit(1);
}
kernel_size = get_file_size(f);
if (!kernel_size ||
fread(header, 1, MIN(ARRAY_SIZE(header), kernel_size), f) !=
MIN(ARRAY_SIZE(header), kernel_size)) {
fprintf(stderr, "qemu: could not load kernel '%s': %s\n",
kernel_filename, strerror(errno));
exit(1);
}
/* kernel protocol version */
if (ldl_p(header + 0x202) == 0x53726448) {
protocol = lduw_p(header + 0x206);
} else {
/*
* This could be a multiboot kernel. If it is, let's stop treating it
* like a Linux kernel.
* Note: some multiboot images could be in the ELF format (the same of
* PVH), so we try multiboot first since we check the multiboot magic
* header before to load it.
*/
if (load_multiboot(fw_cfg, f, kernel_filename, initrd_filename,
kernel_cmdline, kernel_size, header)) {
return;
}
/*
* Check if the file is an uncompressed kernel file (ELF) and load it,
* saving the PVH entry point used by the x86/HVM direct boot ABI.
* If load_elfboot() is successful, populate the fw_cfg info.
*/
if (pvh_enabled &&
load_elfboot(kernel_filename, kernel_size,
header, pvh_start_addr, fw_cfg)) {
fclose(f);
fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE,
strlen(kernel_cmdline) + 1);
fw_cfg_add_string(fw_cfg, FW_CFG_CMDLINE_DATA, kernel_cmdline);
fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_SIZE, sizeof(header));
fw_cfg_add_bytes(fw_cfg, FW_CFG_SETUP_DATA,
header, sizeof(header));
/* load initrd */
if (initrd_filename) {
GMappedFile *mapped_file;
gsize initrd_size;
gchar *initrd_data;
GError *gerr = NULL;
mapped_file = g_mapped_file_new(initrd_filename, false, &gerr);
if (!mapped_file) {
fprintf(stderr, "qemu: error reading initrd %s: %s\n",
initrd_filename, gerr->message);
exit(1);
}
x86ms->initrd_mapped_file = mapped_file;
initrd_data = g_mapped_file_get_contents(mapped_file);
initrd_size = g_mapped_file_get_length(mapped_file);
initrd_max = x86ms->below_4g_mem_size - acpi_data_size - 1;
if (initrd_size >= initrd_max) {
fprintf(stderr, "qemu: initrd is too large, cannot support."
"(max: %"PRIu32", need %"PRId64")\n",
initrd_max, (uint64_t)initrd_size);
exit(1);
}
initrd_addr = (initrd_max - initrd_size) & ~4095;
fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, initrd_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, initrd_size);
fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, initrd_data,
initrd_size);
}
option_rom[nb_option_roms].bootindex = 0;
option_rom[nb_option_roms].name = "pvh.bin";
nb_option_roms++;
return;
}
protocol = 0;
}
if (protocol < 0x200 || !(header[0x211] & 0x01)) {
/* Low kernel */
real_addr = 0x90000;
cmdline_addr = 0x9a000 - cmdline_size;
prot_addr = 0x10000;
} else if (protocol < 0x202) {
/* High but ancient kernel */
real_addr = 0x90000;
cmdline_addr = 0x9a000 - cmdline_size;
prot_addr = 0x100000;
} else {
/* High and recent kernel */
real_addr = 0x10000;
cmdline_addr = 0x20000;
prot_addr = 0x100000;
}
/* highest address for loading the initrd */
if (protocol >= 0x20c &&
lduw_p(header + 0x236) & XLF_CAN_BE_LOADED_ABOVE_4G) {
/*
* Linux has supported initrd up to 4 GB for a very long time (2007,
* long before XLF_CAN_BE_LOADED_ABOVE_4G which was added in 2013),
* though it only sets initrd_max to 2 GB to "work around bootloader
* bugs". Luckily, QEMU firmware(which does something like bootloader)
* has supported this.
*
* It's believed that if XLF_CAN_BE_LOADED_ABOVE_4G is set, initrd can
* be loaded into any address.
*
* In addition, initrd_max is uint32_t simply because QEMU doesn't
* support the 64-bit boot protocol (specifically the ext_ramdisk_image
* field).
*
* Therefore here just limit initrd_max to UINT32_MAX simply as well.
*/
initrd_max = UINT32_MAX;
} else if (protocol >= 0x203) {
initrd_max = ldl_p(header + 0x22c);
} else {
initrd_max = 0x37ffffff;
}
if (initrd_max >= x86ms->below_4g_mem_size - acpi_data_size) {
initrd_max = x86ms->below_4g_mem_size - acpi_data_size - 1;
}
fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_ADDR, cmdline_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE, strlen(kernel_cmdline) + 1);
fw_cfg_add_string(fw_cfg, FW_CFG_CMDLINE_DATA, kernel_cmdline);
if (protocol >= 0x202) {
stl_p(header + 0x228, cmdline_addr);
} else {
stw_p(header + 0x20, 0xA33F);
stw_p(header + 0x22, cmdline_addr - real_addr);
}
/* handle vga= parameter */
vmode = strstr(kernel_cmdline, "vga=");
if (vmode) {
unsigned int video_mode;
const char *end;
int ret;
/* skip "vga=" */
vmode += 4;
if (!strncmp(vmode, "normal", 6)) {
video_mode = 0xffff;
} else if (!strncmp(vmode, "ext", 3)) {
video_mode = 0xfffe;
} else if (!strncmp(vmode, "ask", 3)) {
video_mode = 0xfffd;
} else {
ret = qemu_strtoui(vmode, &end, 0, &video_mode);
if (ret != 0 || (*end && *end != ' ')) {
fprintf(stderr, "qemu: invalid 'vga=' kernel parameter.\n");
exit(1);
}
}
stw_p(header + 0x1fa, video_mode);
}
/* loader type */
/*
* High nybble = B reserved for QEMU; low nybble is revision number.
* If this code is substantially changed, you may want to consider
* incrementing the revision.
*/
if (protocol >= 0x200) {
header[0x210] = 0xB0;
}
/* heap */
if (protocol >= 0x201) {
header[0x211] |= 0x80; /* CAN_USE_HEAP */
stw_p(header + 0x224, cmdline_addr - real_addr - 0x200);
}
/* load initrd */
if (initrd_filename) {
GMappedFile *mapped_file;
gsize initrd_size;
gchar *initrd_data;
GError *gerr = NULL;
if (protocol < 0x200) {
fprintf(stderr, "qemu: linux kernel too old to load a ram disk\n");
exit(1);
}
mapped_file = g_mapped_file_new(initrd_filename, false, &gerr);
if (!mapped_file) {
fprintf(stderr, "qemu: error reading initrd %s: %s\n",
initrd_filename, gerr->message);
exit(1);
}
x86ms->initrd_mapped_file = mapped_file;
initrd_data = g_mapped_file_get_contents(mapped_file);
initrd_size = g_mapped_file_get_length(mapped_file);
if (initrd_size >= initrd_max) {
fprintf(stderr, "qemu: initrd is too large, cannot support."
"(max: %"PRIu32", need %"PRId64")\n",
initrd_max, (uint64_t)initrd_size);
exit(1);
}
initrd_addr = (initrd_max - initrd_size) & ~4095;
fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, initrd_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, initrd_size);
fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, initrd_data, initrd_size);
stl_p(header + 0x218, initrd_addr);
stl_p(header + 0x21c, initrd_size);
}
/* load kernel and setup */
setup_size = header[0x1f1];
if (setup_size == 0) {
setup_size = 4;
}
setup_size = (setup_size + 1) * 512;
if (setup_size > kernel_size) {
fprintf(stderr, "qemu: invalid kernel header\n");
exit(1);
}
kernel_size -= setup_size;
setup = g_malloc(setup_size);
kernel = g_malloc(kernel_size);
fseek(f, 0, SEEK_SET);
if (fread(setup, 1, setup_size, f) != setup_size) {
fprintf(stderr, "fread() failed\n");
exit(1);
}
if (fread(kernel, 1, kernel_size, f) != kernel_size) {
fprintf(stderr, "fread() failed\n");
exit(1);
}
fclose(f);
/* append dtb to kernel */
if (dtb_filename) {
if (protocol < 0x209) {
fprintf(stderr, "qemu: Linux kernel too old to load a dtb\n");
exit(1);
}
dtb_size = get_image_size(dtb_filename);
if (dtb_size <= 0) {
fprintf(stderr, "qemu: error reading dtb %s: %s\n",
dtb_filename, strerror(errno));
exit(1);
}
setup_data_offset = QEMU_ALIGN_UP(kernel_size, 16);
kernel_size = setup_data_offset + sizeof(struct setup_data) + dtb_size;
kernel = g_realloc(kernel, kernel_size);
stq_p(header + 0x250, prot_addr + setup_data_offset);
setup_data = (struct setup_data *)(kernel + setup_data_offset);
setup_data->next = 0;
setup_data->type = cpu_to_le32(SETUP_DTB);
setup_data->len = cpu_to_le32(dtb_size);
load_image_size(dtb_filename, setup_data->data, dtb_size);
}
memcpy(setup, header, MIN(sizeof(header), setup_size));
fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, prot_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, kernel_size);
fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, kernel, kernel_size);
fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_ADDR, real_addr);
fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_SIZE, setup_size);
fw_cfg_add_bytes(fw_cfg, FW_CFG_SETUP_DATA, setup, setup_size);
option_rom[nb_option_roms].bootindex = 0;
option_rom[nb_option_roms].name = "linuxboot.bin";
if (linuxboot_dma_enabled && fw_cfg_dma_enabled(fw_cfg)) {
option_rom[nb_option_roms].name = "linuxboot_dma.bin";
}
nb_option_roms++;
}
void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
MemoryRegion *rom_memory, bool isapc_ram_fw)
{
const char *bios_name;
char *filename;
MemoryRegion *bios, *isa_bios;
int bios_size, isa_bios_size;
int ret;
/* BIOS load */
bios_name = ms->firmware ?: default_firmware;
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (filename) {
bios_size = get_image_size(filename);
} else {
bios_size = -1;
}
if (bios_size <= 0 ||
(bios_size % 65536) != 0) {
goto bios_error;
}
bios = g_malloc(sizeof(*bios));
memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
if (!isapc_ram_fw) {
memory_region_set_readonly(bios, true);
}
ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
if (ret != 0) {
bios_error:
fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
exit(1);
}
g_free(filename);
/* map the last 128KB of the BIOS in ISA space */
isa_bios_size = MIN(bios_size, 128 * KiB);
isa_bios = g_malloc(sizeof(*isa_bios));
memory_region_init_alias(isa_bios, NULL, "isa-bios", bios,
bios_size - isa_bios_size, isa_bios_size);
memory_region_add_subregion_overlap(rom_memory,
0x100000 - isa_bios_size,
isa_bios,
1);
if (!isapc_ram_fw) {
memory_region_set_readonly(isa_bios, true);
}
/* map all the bios at the top of memory */
memory_region_add_subregion(rom_memory,
(uint32_t)(-bios_size),
bios);
}
bool x86_machine_is_smm_enabled(const X86MachineState *x86ms)
{
bool smm_available = false;
if (x86ms->smm == ON_OFF_AUTO_OFF) {
return false;
}
if (tcg_enabled() || qtest_enabled()) {
smm_available = true;
} else if (kvm_enabled()) {
smm_available = kvm_has_smm();
}
if (smm_available) {
return true;
}
if (x86ms->smm == ON_OFF_AUTO_ON) {
error_report("System Management Mode not supported by this hypervisor.");
exit(1);
}
return false;
}
static void x86_machine_get_smm(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
OnOffAuto smm = x86ms->smm;
visit_type_OnOffAuto(v, name, &smm, errp);
}
static void x86_machine_set_smm(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
visit_type_OnOffAuto(v, name, &x86ms->smm, errp);
}
bool x86_machine_is_acpi_enabled(const X86MachineState *x86ms)
{
if (x86ms->acpi == ON_OFF_AUTO_OFF) {
return false;
}
return true;
}
static void x86_machine_get_acpi(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
OnOffAuto acpi = x86ms->acpi;
visit_type_OnOffAuto(v, name, &acpi, errp);
}
static void x86_machine_set_acpi(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
visit_type_OnOffAuto(v, name, &x86ms->acpi, errp);
}
static char *x86_machine_get_oem_id(Object *obj, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
return g_strdup(x86ms->oem_id);
}
static void x86_machine_set_oem_id(Object *obj, const char *value, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
size_t len = strlen(value);
if (len > 6) {
error_setg(errp,
"User specified "X86_MACHINE_OEM_ID" value is bigger than "
"6 bytes in size");
return;
}
strncpy(x86ms->oem_id, value, 6);
}
static char *x86_machine_get_oem_table_id(Object *obj, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
return g_strdup(x86ms->oem_table_id);
}
static void x86_machine_set_oem_table_id(Object *obj, const char *value,
Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
size_t len = strlen(value);
if (len > 8) {
error_setg(errp,
"User specified "X86_MACHINE_OEM_TABLE_ID
" value is bigger than "
"8 bytes in size");
return;
}
strncpy(x86ms->oem_table_id, value, 8);
}
static void x86_machine_get_bus_lock_ratelimit(Object *obj, Visitor *v,
const char *name, void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
uint64_t bus_lock_ratelimit = x86ms->bus_lock_ratelimit;
visit_type_uint64(v, name, &bus_lock_ratelimit, errp);
}
static void x86_machine_set_bus_lock_ratelimit(Object *obj, Visitor *v,
const char *name, void *opaque, Error **errp)
{
X86MachineState *x86ms = X86_MACHINE(obj);
visit_type_uint64(v, name, &x86ms->bus_lock_ratelimit, errp);
}
static void x86_machine_initfn(Object *obj)
{
X86MachineState *x86ms = X86_MACHINE(obj);
x86ms->smm = ON_OFF_AUTO_AUTO;
x86ms->acpi = ON_OFF_AUTO_AUTO;
x86ms->smp_dies = 1;
x86ms->pci_irq_mask = ACPI_BUILD_PCI_IRQS;
x86ms->oem_id = g_strndup(ACPI_BUILD_APPNAME6, 6);
x86ms->oem_table_id = g_strndup(ACPI_BUILD_APPNAME8, 8);
x86ms->bus_lock_ratelimit = 0;
}
static void x86_machine_class_init(ObjectClass *oc, void *data)
{
MachineClass *mc = MACHINE_CLASS(oc);
X86MachineClass *x86mc = X86_MACHINE_CLASS(oc);
NMIClass *nc = NMI_CLASS(oc);
mc->cpu_index_to_instance_props = x86_cpu_index_to_props;
mc->get_default_cpu_node_id = x86_get_default_cpu_node_id;
mc->possible_cpu_arch_ids = x86_possible_cpu_arch_ids;
x86mc->compat_apic_id_mode = false;
x86mc->save_tsc_khz = true;
nc->nmi_monitor_handler = x86_nmi;
object_class_property_add(oc, X86_MACHINE_SMM, "OnOffAuto",
x86_machine_get_smm, x86_machine_set_smm,
NULL, NULL);
object_class_property_set_description(oc, X86_MACHINE_SMM,
"Enable SMM");
object_class_property_add(oc, X86_MACHINE_ACPI, "OnOffAuto",
x86_machine_get_acpi, x86_machine_set_acpi,
NULL, NULL);
object_class_property_set_description(oc, X86_MACHINE_ACPI,
"Enable ACPI");
object_class_property_add_str(oc, X86_MACHINE_OEM_ID,
x86_machine_get_oem_id,
x86_machine_set_oem_id);
object_class_property_set_description(oc, X86_MACHINE_OEM_ID,
"Override the default value of field OEMID "
"in ACPI table header."
"The string may be up to 6 bytes in size");
object_class_property_add_str(oc, X86_MACHINE_OEM_TABLE_ID,
x86_machine_get_oem_table_id,
x86_machine_set_oem_table_id);
object_class_property_set_description(oc, X86_MACHINE_OEM_TABLE_ID,
"Override the default value of field OEM Table ID "
"in ACPI table header."
"The string may be up to 8 bytes in size");
object_class_property_add(oc, X86_MACHINE_BUS_LOCK_RATELIMIT, "uint64_t",
x86_machine_get_bus_lock_ratelimit,
x86_machine_set_bus_lock_ratelimit, NULL, NULL);
object_class_property_set_description(oc, X86_MACHINE_BUS_LOCK_RATELIMIT,
"Set the ratelimit for the bus locks acquired in VMs");
}
static const TypeInfo x86_machine_info = {
.name = TYPE_X86_MACHINE,
.parent = TYPE_MACHINE,
.abstract = true,
.instance_size = sizeof(X86MachineState),
.instance_init = x86_machine_initfn,
.class_size = sizeof(X86MachineClass),
.class_init = x86_machine_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_NMI },
{ }
},
};
static void x86_machine_register_types(void)
{
type_register_static(&x86_machine_info);
}
type_init(x86_machine_register_types)