qemu/hw/i386/x86-common.c
Michael Roth fc7a69e177 hw/i386: Add support for loading BIOS using guest_memfd
When guest_memfd is enabled, the BIOS is generally part of the initial
encrypted guest image and will be accessed as private guest memory. Add
the necessary changes to set up the associated RAM region with a
guest_memfd backend to allow for this.

Current support centers around using -bios to load the BIOS data.
Support for loading the BIOS via pflash requires additional enablement
since those interfaces rely on the use of ROM memory regions which make
use of the KVM_MEM_READONLY memslot flag, which is not supported for
guest_memfd-backed memslots.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Pankaj Gupta <pankaj.gupta@amd.com>
Message-ID: <20240530111643.1091816-29-pankaj.gupta@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-06-05 11:01:06 +02:00

1047 lines
35 KiB
C

/*
* Copyright (c) 2003-2004 Fabrice Bellard
* Copyright (c) 2019, 2024 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/cutils.h"
#include "qemu/units.h"
#include "qemu/datadir.h"
#include "qapi/error.h"
#include "sysemu/numa.h"
#include "sysemu/sysemu.h"
#include "sysemu/xen.h"
#include "trace.h"
#include "hw/i386/x86.h"
#include "target/i386/cpu.h"
#include "hw/rtc/mc146818rtc.h"
#include "target/i386/sev.h"
#include "hw/acpi/cpu_hotplug.h"
#include "hw/irq.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"
#ifdef CONFIG_XEN_EMU
#include "hw/xen/xen.h"
#include "hw/i386/kvm/xen_evtchn.h"
#endif
/* Physical Address of PVH entry point read from kernel ELF NOTE */
static size_t pvh_start_addr;
static 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;
/*
* Can we support APIC ID 255 or higher? With KVM, that requires
* both in-kernel lapic and X2APIC userspace API.
*
* kvm_enabled() must go first to ensure that kvm_* references are
* not emitted for the linker to consume (kvm_enabled() is
* a literal `0` in configurations where kvm_* aren't defined)
*/
if (kvm_enabled() && x86ms->apic_id_limit > 255 &&
kvm_irqchip_in_kernel() && !kvm_enable_x2apic()) {
error_report("current -smp configuration requires kernel "
"irqchip and X2APIC API support.");
exit(EXIT_FAILURE);
}
if (kvm_enabled()) {
kvm_set_max_apic_id(x86ms->apic_id_limit);
}
if (!kvm_irqchip_in_kernel()) {
apic_set_max_apic_id(x86ms->apic_id_limit);
}
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 *s, uint16_t cpus_count)
{
MC146818RtcState *rtc = MC146818_RTC(s);
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.
*/
mc146818rtc_set_cmos_data(rtc, 0x5f, 0);
} else {
mc146818rtc_set_cmos_data(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.
*/
static 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 = CPU(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);
if (ms->smp.modules > 1) {
env->nr_modules = ms->smp.modules;
set_bit(CPU_TOPO_LEVEL_MODULE, env->avail_cpu_topo);
}
if (ms->smp.dies > 1) {
env->nr_dies = ms->smp.dies;
set_bit(CPU_TOPO_LEVEL_DIE, env->avail_cpu_topo);
}
/*
* If APIC ID is not set,
* set it based on socket/die/module/core/thread properties.
*/
if (cpu->apic_id == UNASSIGNED_APIC_ID) {
/*
* 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 && ms->smp.dies == 1) {
cpu->die_id = 0;
}
/*
* module-id was optional in QEMU 9.0 and older, so keep it optional
* if there's only one module per die.
*/
if (cpu->module_id < 0 && ms->smp.modules == 1) {
cpu->module_id = 0;
}
if (cpu->socket_id < 0) {
error_setg(errp, "CPU socket-id is not set");
return;
} else if (cpu->socket_id > ms->smp.sockets - 1) {
error_setg(errp, "Invalid CPU socket-id: %u must be in range 0:%u",
cpu->socket_id, ms->smp.sockets - 1);
return;
}
if (cpu->die_id < 0) {
error_setg(errp, "CPU die-id is not set");
return;
} else if (cpu->die_id > ms->smp.dies - 1) {
error_setg(errp, "Invalid CPU die-id: %u must be in range 0:%u",
cpu->die_id, ms->smp.dies - 1);
return;
}
if (cpu->module_id < 0) {
error_setg(errp, "CPU module-id is not set");
return;
} else if (cpu->module_id > ms->smp.modules - 1) {
error_setg(errp, "Invalid CPU module-id: %u must be in range 0:%u",
cpu->module_id, ms->smp.modules - 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.module_id = cpu->module_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) {
x86_topo_ids_from_apicid(cpu->apic_id, &topo_info, &topo_ids);
error_setg(errp,
"Invalid CPU [socket: %u, die: %u, module: %u, core: %u, thread: %u]"
" with APIC ID %" PRIu32 ", valid index range 0:%d",
topo_ids.pkg_id, topo_ids.die_id, topo_ids.module_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->module_id != -1 && cpu->module_id != topo_ids.module_id) {
error_setg(errp, "property module-id: %u doesn't match set apic-id:"
" 0x%x (module-id: %u)", cpu->module_id, cpu->apic_id,
topo_ids.module_id);
return;
}
cpu->module_id = topo_ids.module_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;
/*
* kvm_enabled() must go first to ensure that kvm_* references are
* not emitted for the linker to consume (kvm_enabled() is
* a literal `0` in configurations where kvm_* aren't defined)
*/
if (kvm_enabled() && 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);
}
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;
}
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:
#ifdef CONFIG_XEN_EMU
/*
* Xen delivers the GSI to the Legacy PIC (not that Legacy PIC
* routing actually works properly under Xen). And then to
* *either* the PIRQ handling or the I/OAPIC depending on
* whether the former wants it.
*/
if (xen_mode == XEN_EMULATE && xen_evtchn_set_gsi(n, level)) {
break;
}
#endif
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, Object *parent)
{
DeviceState *dev;
SysBusDevice *d;
unsigned int i;
assert(parent);
if (kvm_ioapic_in_kernel()) {
dev = qdev_new(TYPE_KVM_IOAPIC);
} else {
dev = qdev_new(TYPE_IOAPIC);
}
object_property_add_child(parent, "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;
}
/*
* 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 = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_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;
SevKernelLoaderContext sev_load_ctx = {};
/* 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(x86ms, 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);
sev_load_ctx.cmdline_data = (char *)kernel_cmdline;
sev_load_ctx.cmdline_size = strlen(kernel_cmdline) + 1;
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);
sev_load_ctx.initrd_data = initrd_data;
sev_load_ctx.initrd_size = 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);
}
/*
* If we're starting an encrypted VM, it will be OVMF based, which uses the
* efi stub for booting and doesn't require any values to be placed in the
* kernel header. We therefore don't update the header so the hash of the
* kernel on the other side of the fw_cfg interface matches the hash of the
* file the user passed in.
*/
if (!sev_enabled()) {
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);
sev_load_ctx.kernel_data = (char *)kernel;
sev_load_ctx.kernel_size = 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);
sev_load_ctx.setup_data = (char *)setup;
sev_load_ctx.setup_size = setup_size;
if (sev_enabled()) {
sev_add_kernel_loader_hashes(&sev_load_ctx, &error_fatal);
}
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_isa_bios_init(MemoryRegion *isa_bios, MemoryRegion *isa_memory,
MemoryRegion *bios, bool read_only)
{
uint64_t bios_size = memory_region_size(bios);
uint64_t isa_bios_size = MIN(bios_size, 128 * KiB);
memory_region_init_alias(isa_bios, NULL, "isa-bios", bios,
bios_size - isa_bios_size, isa_bios_size);
memory_region_add_subregion_overlap(isa_memory, 1 * MiB - isa_bios_size,
isa_bios, 1);
memory_region_set_readonly(isa_bios, read_only);
}
void x86_bios_rom_init(X86MachineState *x86ms, const char *default_firmware,
MemoryRegion *rom_memory, bool isapc_ram_fw)
{
const char *bios_name;
char *filename;
int bios_size;
ssize_t ret;
/* BIOS load */
bios_name = MACHINE(x86ms)->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;
}
if (machine_require_guest_memfd(MACHINE(x86ms))) {
memory_region_init_ram_guest_memfd(&x86ms->bios, NULL, "pc.bios",
bios_size, &error_fatal);
} else {
memory_region_init_ram(&x86ms->bios, NULL, "pc.bios",
bios_size, &error_fatal);
}
if (sev_enabled()) {
/*
* The concept of a "reset" simply doesn't exist for
* confidential computing guests, we have to destroy and
* re-launch them instead. So there is no need to register
* the firmware as rom to properly re-initialize on reset.
* Just go for a straight file load instead.
*/
void *ptr = memory_region_get_ram_ptr(&x86ms->bios);
load_image_size(filename, ptr, bios_size);
x86_firmware_configure(0x100000000ULL - bios_size, ptr, bios_size);
} else {
memory_region_set_readonly(&x86ms->bios, !isapc_ram_fw);
ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
if (ret != 0) {
goto bios_error;
}
}
g_free(filename);
if (!machine_require_guest_memfd(MACHINE(x86ms))) {
/* map the last 128KB of the BIOS in ISA space */
x86_isa_bios_init(&x86ms->isa_bios, rom_memory, &x86ms->bios,
!isapc_ram_fw);
}
/* map all the bios at the top of memory */
memory_region_add_subregion(rom_memory,
(uint32_t)(-bios_size),
&x86ms->bios);
return;
bios_error:
fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
exit(1);
}