Re: [PATCH v5 05/28] acpi: Remove legacy cpu hotplug utilities

[Igor Mammedov <imammedo@redhat.com>]

On Wed,  3 Dec 2025 00:28:12 +0800
Zhao Liu <zhao1.liu@intel.com> wrote:

> From: Igor Mammedov <imammedo@redhat.com>
ditto
see 2/28 comment

> 
> The cpu_hotplug.h and cpu_hotplug.c contain legacy cpu hotplug
> utilities. Now there's no use case of legacy cpu hotplug, so it's safe
> to drop legacy cpu hotplug support totally.
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> Signed-off-by: Zhao Liu <zhao1.liu@intel.com>

Acked-by: Igor Mammedov <imammedo@redhat.com>

> ---
> Changes since v4:
>  * New patch split off from Igor's v5 [*].
> 
> [*]: https://lore.kernel.org/qemu-devel/20251031142825.179239-1-imammedo@redhat.com/
> ---
>  hw/acpi/acpi-cpu-hotplug-stub.c |  19 +-
>  hw/acpi/cpu_hotplug.c           | 348 --------------------------------
>  hw/acpi/generic_event_device.c  |   1 +
>  hw/acpi/ich9.c                  |   1 +
>  hw/acpi/meson.build             |   2 +-
>  hw/acpi/piix4.c                 |   2 +-
>  hw/i386/acpi-build.c            |   1 +
>  hw/i386/pc.c                    |   3 +-
>  hw/i386/x86-common.c            |   1 -
>  include/hw/acpi/cpu_hotplug.h   |  40 ----
>  include/hw/acpi/ich9.h          |   2 +-
>  include/hw/acpi/piix4.h         |   2 +-
>  12 files changed, 10 insertions(+), 412 deletions(-)
>  delete mode 100644 hw/acpi/cpu_hotplug.c
>  delete mode 100644 include/hw/acpi/cpu_hotplug.h
> 
> diff --git a/hw/acpi/acpi-cpu-hotplug-stub.c b/hw/acpi/acpi-cpu-hotplug-stub.c
> index 9872dd55e43f..72c5f05f5c4e 100644
> --- a/hw/acpi/acpi-cpu-hotplug-stub.c
> +++ b/hw/acpi/acpi-cpu-hotplug-stub.c
> @@ -1,22 +1,10 @@
>  #include "qemu/osdep.h"
> -#include "hw/acpi/cpu_hotplug.h"
>  #include "migration/vmstate.h"
> -
> +#include "hw/acpi/cpu.h"
>  
>  /* Following stubs are all related to ACPI cpu hotplug */
>  const VMStateDescription vmstate_cpu_hotplug;
>  
> -void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu,
> -                                CPUHotplugState *cpuhp_state,
> -                                uint16_t io_port)
> -{
> -}
> -
> -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> -                                  AcpiCpuHotplug *gpe_cpu, uint16_t base)
> -{
> -}
> -
>  void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
>                           CPUHotplugState *state, hwaddr base_addr)
>  {
> @@ -31,11 +19,6 @@ void acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
>  {
>  }
>  
> -void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
> -                             AcpiCpuHotplug *g, DeviceState *dev, Error **errp)
> -{
> -}
> -
>  void acpi_cpu_unplug_cb(CPUHotplugState *cpu_st,
>                          DeviceState *dev, Error **errp)
>  {
> diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c
> deleted file mode 100644
> index aa0e1e3efa54..000000000000
> --- a/hw/acpi/cpu_hotplug.c
> +++ /dev/null
> @@ -1,348 +0,0 @@
> -/*
> - * QEMU ACPI hotplug utilities
> - *
> - * Copyright (C) 2013 Red Hat Inc
> - *
> - * Authors:
> - *   Igor Mammedov <imammedo@redhat.com>
> - *
> - * This work is licensed under the terms of the GNU GPL, version 2 or later.
> - * See the COPYING file in the top-level directory.
> - */
> -#include "qemu/osdep.h"
> -#include "hw/acpi/cpu_hotplug.h"
> -#include "qapi/error.h"
> -#include "hw/core/cpu.h"
> -#include "hw/i386/x86.h"
> -#include "hw/pci/pci_device.h"
> -#include "qemu/error-report.h"
> -
> -#define CPU_EJECT_METHOD "CPEJ"
> -#define CPU_MAT_METHOD "CPMA"
> -#define CPU_ON_BITMAP "CPON"
> -#define CPU_STATUS_METHOD "CPST"
> -#define CPU_STATUS_MAP "PRS"
> -#define CPU_SCAN_METHOD "PRSC"
> -
> -static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size)
> -{
> -    AcpiCpuHotplug *cpus = opaque;
> -    uint64_t val = cpus->sts[addr];
> -
> -    return val;
> -}
> -
> -static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data,
> -                             unsigned int size)
> -{
> -    /* firmware never used to write in CPU present bitmap so use
> -       this fact as means to switch QEMU into modern CPU hotplug
> -       mode by writing 0 at the beginning of legacy CPU bitmap
> -     */
> -    if (addr == 0 && data == 0) {
> -        AcpiCpuHotplug *cpus = opaque;
> -        object_property_set_bool(cpus->device, "cpu-hotplug-legacy", false,
> -                                 &error_abort);
> -    }
> -}
> -
> -static const MemoryRegionOps AcpiCpuHotplug_ops = {
> -    .read = cpu_status_read,
> -    .write = cpu_status_write,
> -    .endianness = DEVICE_LITTLE_ENDIAN,
> -    .valid = {
> -        .min_access_size = 1,
> -        .max_access_size = 4,
> -    },
> -    .impl = {
> -        .max_access_size = 1,
> -    },
> -};
> -
> -static void acpi_set_cpu_present_bit(AcpiCpuHotplug *g, CPUState *cpu,
> -                                     bool *swtchd_to_modern)
> -{
> -    int64_t cpu_id;
> -
> -    cpu_id = cpu->cc->get_arch_id(cpu);
> -    if ((cpu_id / 8) >= ACPI_GPE_PROC_LEN) {
> -        object_property_set_bool(g->device, "cpu-hotplug-legacy", false,
> -                                 &error_abort);
> -        *swtchd_to_modern = true;
> -        return;
> -    }
> -
> -    *swtchd_to_modern = false;
> -    g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
> -}
> -
> -void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
> -                             AcpiCpuHotplug *g, DeviceState *dev, Error **errp)
> -{
> -    bool swtchd_to_modern;
> -    Error *local_err = NULL;
> -
> -    acpi_set_cpu_present_bit(g, CPU(dev), &swtchd_to_modern);
> -    if (swtchd_to_modern) {
> -        /* propagate the hotplug to the modern interface */
> -        hotplug_handler_plug(hotplug_dev, dev, &local_err);
> -    } else {
> -        acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
> -    }
> -}
> -
> -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> -                                  AcpiCpuHotplug *gpe_cpu, uint16_t base)
> -{
> -    CPUState *cpu;
> -    bool swtchd_to_modern;
> -
> -    memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops,
> -                          gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN);
> -    memory_region_add_subregion(parent, base, &gpe_cpu->io);
> -    gpe_cpu->device = owner;
> -
> -    CPU_FOREACH(cpu) {
> -        acpi_set_cpu_present_bit(gpe_cpu, cpu, &swtchd_to_modern);
> -    }
> -}
> -
> -void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu,
> -                                CPUHotplugState *cpuhp_state,
> -                                uint16_t io_port)
> -{
> -    MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device));
> -
> -    memory_region_del_subregion(parent, &gpe_cpu->io);
> -    cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port);
> -}
> -
> -void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine,
> -                                  uint16_t io_base)
> -{
> -    Aml *dev;
> -    Aml *crs;
> -    Aml *pkg;
> -    Aml *field;
> -    Aml *method;
> -    Aml *if_ctx;
> -    Aml *else_ctx;
> -    int i, apic_idx;
> -    Aml *sb_scope = aml_scope("_SB");
> -    uint8_t madt_tmpl[8] = {0x00, 0x08, 0x00, 0x00, 0x00, 0, 0, 0};
> -    Aml *cpu_id = aml_arg(1);
> -    Aml *apic_id = aml_arg(0);
> -    Aml *cpu_on = aml_local(0);
> -    Aml *madt = aml_local(1);
> -    Aml *cpus_map = aml_name(CPU_ON_BITMAP);
> -    Aml *zero = aml_int(0);
> -    Aml *one = aml_int(1);
> -    MachineClass *mc = MACHINE_GET_CLASS(machine);
> -    const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(machine);
> -    X86MachineState *x86ms = X86_MACHINE(machine);
> -
> -    /*
> -     * _MAT method - creates an madt apic buffer
> -     * apic_id = Arg0 = Local APIC ID
> -     * cpu_id  = Arg1 = Processor ID
> -     * cpu_on = Local0 = CPON flag for this cpu
> -     * madt = Local1 = Buffer (in madt apic form) to return
> -     */
> -    method = aml_method(CPU_MAT_METHOD, 2, AML_NOTSERIALIZED);
> -    aml_append(method,
> -        aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on));
> -    aml_append(method,
> -        aml_store(aml_buffer(sizeof(madt_tmpl), madt_tmpl), madt));
> -    /* Update the processor id, lapic id, and enable/disable status */
> -    aml_append(method, aml_store(cpu_id, aml_index(madt, aml_int(2))));
> -    aml_append(method, aml_store(apic_id, aml_index(madt, aml_int(3))));
> -    aml_append(method, aml_store(cpu_on, aml_index(madt, aml_int(4))));
> -    aml_append(method, aml_return(madt));
> -    aml_append(sb_scope, method);
> -
> -    /*
> -     * _STA method - return ON status of cpu
> -     * apic_id = Arg0 = Local APIC ID
> -     * cpu_on = Local0 = CPON flag for this cpu
> -     */
> -    method = aml_method(CPU_STATUS_METHOD, 1, AML_NOTSERIALIZED);
> -    aml_append(method,
> -        aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on));
> -    if_ctx = aml_if(cpu_on);
> -    {
> -        aml_append(if_ctx, aml_return(aml_int(0xF)));
> -    }
> -    aml_append(method, if_ctx);
> -    else_ctx = aml_else();
> -    {
> -        aml_append(else_ctx, aml_return(zero));
> -    }
> -    aml_append(method, else_ctx);
> -    aml_append(sb_scope, method);
> -
> -    method = aml_method(CPU_EJECT_METHOD, 2, AML_NOTSERIALIZED);
> -    aml_append(method, aml_sleep(200));
> -    aml_append(sb_scope, method);
> -
> -    method = aml_method(CPU_SCAN_METHOD, 0, AML_NOTSERIALIZED);
> -    {
> -        Aml *while_ctx, *if_ctx2, *else_ctx2;
> -        Aml *bus_check_evt = aml_int(1);
> -        Aml *remove_evt = aml_int(3);
> -        Aml *status_map = aml_local(5); /* Local5 = active cpu bitmap */
> -        Aml *byte = aml_local(2); /* Local2 = last read byte from bitmap */
> -        Aml *idx = aml_local(0); /* Processor ID / APIC ID iterator */
> -        Aml *is_cpu_on = aml_local(1); /* Local1 = CPON flag for cpu */
> -        Aml *status = aml_local(3); /* Local3 = active state for cpu */
> -
> -        aml_append(method, aml_store(aml_name(CPU_STATUS_MAP), status_map));
> -        aml_append(method, aml_store(zero, byte));
> -        aml_append(method, aml_store(zero, idx));
> -
> -        /* While (idx < SizeOf(CPON)) */
> -        while_ctx = aml_while(aml_lless(idx, aml_sizeof(cpus_map)));
> -        aml_append(while_ctx,
> -            aml_store(aml_derefof(aml_index(cpus_map, idx)), is_cpu_on));
> -
> -        if_ctx = aml_if(aml_and(idx, aml_int(0x07), NULL));
> -        {
> -            /* Shift down previously read bitmap byte */
> -            aml_append(if_ctx, aml_shiftright(byte, one, byte));
> -        }
> -        aml_append(while_ctx, if_ctx);
> -
> -        else_ctx = aml_else();
> -        {
> -            /* Read next byte from cpu bitmap */
> -            aml_append(else_ctx, aml_store(aml_derefof(aml_index(status_map,
> -                       aml_shiftright(idx, aml_int(3), NULL))), byte));
> -        }
> -        aml_append(while_ctx, else_ctx);
> -
> -        aml_append(while_ctx, aml_store(aml_and(byte, one, NULL), status));
> -        if_ctx = aml_if(aml_lnot(aml_equal(is_cpu_on, status)));
> -        {
> -            /* State change - update CPON with new state */
> -            aml_append(if_ctx, aml_store(status, aml_index(cpus_map, idx)));
> -            if_ctx2 = aml_if(aml_equal(status, one));
> -            {
> -                aml_append(if_ctx2,
> -                    aml_call2(AML_NOTIFY_METHOD, idx, bus_check_evt));
> -            }
> -            aml_append(if_ctx, if_ctx2);
> -            else_ctx2 = aml_else();
> -            {
> -                aml_append(else_ctx2,
> -                    aml_call2(AML_NOTIFY_METHOD, idx, remove_evt));
> -            }
> -        }
> -        aml_append(if_ctx, else_ctx2);
> -        aml_append(while_ctx, if_ctx);
> -
> -        aml_append(while_ctx, aml_increment(idx)); /* go to next cpu */
> -        aml_append(method, while_ctx);
> -    }
> -    aml_append(sb_scope, method);
> -
> -    /* The current AML generator can cover the APIC ID range [0..255],
> -     * inclusive, for VCPU hotplug. */
> -    QEMU_BUILD_BUG_ON(ACPI_CPU_HOTPLUG_ID_LIMIT > 256);
> -    if (x86ms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) {
> -        error_report("max_cpus is too large. APIC ID of last CPU is %u",
> -                     x86ms->apic_id_limit - 1);
> -        exit(1);
> -    }
> -
> -    /* create PCI0.PRES device and its _CRS to reserve CPU hotplug MMIO */
> -    dev = aml_device("PCI0." stringify(CPU_HOTPLUG_RESOURCE_DEVICE));
> -    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A06")));
> -    aml_append(dev,
> -        aml_name_decl("_UID", aml_string("CPU Hotplug resources"))
> -    );
> -    /* device present, functioning, decoding, not shown in UI */
> -    aml_append(dev, aml_name_decl("_STA", aml_int(0xB)));
> -    crs = aml_resource_template();
> -    aml_append(crs,
> -        aml_io(AML_DECODE16, io_base, io_base, 1, ACPI_GPE_PROC_LEN)
> -    );
> -    aml_append(dev, aml_name_decl("_CRS", crs));
> -    aml_append(sb_scope, dev);
> -    /* declare CPU hotplug MMIO region and PRS field to access it */
> -    aml_append(sb_scope, aml_operation_region(
> -        "PRST", AML_SYSTEM_IO, aml_int(io_base), ACPI_GPE_PROC_LEN));
> -    field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
> -    aml_append(field, aml_named_field("PRS", 256));
> -    aml_append(sb_scope, field);
> -
> -    /* build Processor object for each processor */
> -    for (i = 0; i < apic_ids->len; i++) {
> -        int cpu_apic_id = apic_ids->cpus[i].arch_id;
> -
> -        assert(cpu_apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT);
> -
> -        dev = aml_processor(i, 0, 0, "CP%.02X", cpu_apic_id);
> -
> -        method = aml_method("_MAT", 0, AML_NOTSERIALIZED);
> -        aml_append(method,
> -            aml_return(aml_call2(CPU_MAT_METHOD,
> -                                 aml_int(cpu_apic_id), aml_int(i))
> -        ));
> -        aml_append(dev, method);
> -
> -        method = aml_method("_STA", 0, AML_NOTSERIALIZED);
> -        aml_append(method,
> -            aml_return(aml_call1(CPU_STATUS_METHOD, aml_int(cpu_apic_id))));
> -        aml_append(dev, method);
> -
> -        method = aml_method("_EJ0", 1, AML_NOTSERIALIZED);
> -        aml_append(method,
> -            aml_return(aml_call2(CPU_EJECT_METHOD, aml_int(cpu_apic_id),
> -                aml_arg(0)))
> -        );
> -        aml_append(dev, method);
> -
> -        aml_append(sb_scope, dev);
> -    }
> -
> -    /* build this code:
> -     *   Method(NTFY, 2) {If (LEqual(Arg0, 0x00)) {Notify(CP00, Arg1)} ...}
> -     */
> -    /* Arg0 = APIC ID */
> -    method = aml_method(AML_NOTIFY_METHOD, 2, AML_NOTSERIALIZED);
> -    for (i = 0; i < apic_ids->len; i++) {
> -        int cpu_apic_id = apic_ids->cpus[i].arch_id;
> -
> -        if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(cpu_apic_id)));
> -        aml_append(if_ctx,
> -            aml_notify(aml_name("CP%.02X", cpu_apic_id), aml_arg(1))
> -        );
> -        aml_append(method, if_ctx);
> -    }
> -    aml_append(sb_scope, method);
> -
> -    /* build "Name(CPON, Package() { One, One, ..., Zero, Zero, ... })"
> -     *
> -     * Note: The ability to create variable-sized packages was first
> -     * introduced in ACPI 2.0. ACPI 1.0 only allowed fixed-size packages
> -     * ith up to 255 elements. Windows guests up to win2k8 fail when
> -     * VarPackageOp is used.
> -     */
> -    pkg = x86ms->apic_id_limit <= 255 ? aml_package(x86ms->apic_id_limit) :
> -                                        aml_varpackage(x86ms->apic_id_limit);
> -
> -    for (i = 0, apic_idx = 0; i < apic_ids->len; i++) {
> -        int cpu_apic_id = apic_ids->cpus[i].arch_id;
> -
> -        for (; apic_idx < cpu_apic_id; apic_idx++) {
> -            aml_append(pkg, aml_int(0));
> -        }
> -        aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0));
> -        apic_idx = cpu_apic_id + 1;
> -    }
> -    aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg));
> -    aml_append(ctx, sb_scope);
> -
> -    method = aml_method("\\_GPE._E02", 0, AML_NOTSERIALIZED);
> -    aml_append(method, aml_call0("\\_SB." CPU_SCAN_METHOD));
> -    aml_append(ctx, method);
> -}
> diff --git a/hw/acpi/generic_event_device.c b/hw/acpi/generic_event_device.c
> index e7b773d84d50..9d0962d60203 100644
> --- a/hw/acpi/generic_event_device.c
> +++ b/hw/acpi/generic_event_device.c
> @@ -13,6 +13,7 @@
>  #include "qapi/error.h"
>  #include "hw/acpi/acpi.h"
>  #include "hw/acpi/pcihp.h"
> +#include "hw/acpi/cpu.h"
>  #include "hw/acpi/generic_event_device.h"
>  #include "hw/pci/pci.h"
>  #include "hw/irq.h"
> diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
> index f254f3879716..bbb1bd60a206 100644
> --- a/hw/acpi/ich9.c
> +++ b/hw/acpi/ich9.c
> @@ -40,6 +40,7 @@
>  #include "hw/southbridge/ich9.h"
>  #include "hw/mem/pc-dimm.h"
>  #include "hw/mem/nvdimm.h"
> +#include "hw/acpi/pc-hotplug.h"
>  
>  static void ich9_pm_update_sci_fn(ACPIREGS *regs)
>  {
> diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
> index 56b5d1ec9691..66c978aae836 100644
> --- a/hw/acpi/meson.build
> +++ b/hw/acpi/meson.build
> @@ -6,7 +6,7 @@ acpi_ss.add(files(
>    'core.c',
>    'utils.c',
>  ))
> -acpi_ss.add(when: 'CONFIG_ACPI_CPU_HOTPLUG', if_true: files('cpu.c', 'cpu_hotplug.c'))
> +acpi_ss.add(when: 'CONFIG_ACPI_CPU_HOTPLUG', if_true: files('cpu.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_CPU_HOTPLUG', if_false: files('acpi-cpu-hotplug-stub.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_MEMORY_HOTPLUG', if_true: files('memory_hotplug.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_MEMORY_HOTPLUG', if_false: files('acpi-mem-hotplug-stub.c'))
> diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> index 6ad5f1d1c19d..87a2e4a68247 100644
> --- a/hw/acpi/piix4.c
> +++ b/hw/acpi/piix4.c
> @@ -33,7 +33,6 @@
>  #include "system/xen.h"
>  #include "qapi/error.h"
>  #include "qemu/range.h"
> -#include "hw/acpi/cpu_hotplug.h"
>  #include "hw/acpi/cpu.h"
>  #include "hw/hotplug.h"
>  #include "hw/mem/pc-dimm.h"
> @@ -43,6 +42,7 @@
>  #include "migration/vmstate.h"
>  #include "hw/core/cpu.h"
>  #include "qom/object.h"
> +#include "hw/acpi/pc-hotplug.h"
>  
>  #define GPE_BASE 0xafe0
>  #define GPE_LEN 4
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index bf7ed2e50837..a744eb6c3a9b 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -35,6 +35,7 @@
>  #include "hw/acpi/acpi-defs.h"
>  #include "hw/acpi/acpi.h"
>  #include "hw/acpi/cpu.h"
> +#include "hw/acpi/pc-hotplug.h"
>  #include "hw/nvram/fw_cfg.h"
>  #include "hw/acpi/bios-linker-loader.h"
>  #include "hw/acpi/acpi_aml_interface.h"
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index f8b919cb6c47..2b8d3982c4a0 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -48,7 +48,8 @@
>  #include "hw/xen/xen.h"
>  #include "qobject/qlist.h"
>  #include "qemu/error-report.h"
> -#include "hw/acpi/cpu_hotplug.h"
> +#include "hw/acpi/acpi.h"
> +#include "hw/acpi/pc-hotplug.h"
>  #include "acpi-build.h"
>  #include "hw/mem/nvdimm.h"
>  #include "hw/cxl/cxl_host.h"
> diff --git a/hw/i386/x86-common.c b/hw/i386/x86-common.c
> index c844749900a3..60b7ab80433a 100644
> --- a/hw/i386/x86-common.c
> +++ b/hw/i386/x86-common.c
> @@ -36,7 +36,6 @@
>  #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"
> diff --git a/include/hw/acpi/cpu_hotplug.h b/include/hw/acpi/cpu_hotplug.h
> deleted file mode 100644
> index 3b932abbbbee..000000000000
> --- a/include/hw/acpi/cpu_hotplug.h
> +++ /dev/null
> @@ -1,40 +0,0 @@
> -/*
> - * QEMU ACPI hotplug utilities
> - *
> - * Copyright (C) 2013 Red Hat Inc
> - *
> - * Authors:
> - *   Igor Mammedov <imammedo@redhat.com>
> - *
> - * This work is licensed under the terms of the GNU GPL, version 2 or later.
> - * See the COPYING file in the top-level directory.
> - */
> -
> -#ifndef HW_ACPI_CPU_HOTPLUG_H
> -#define HW_ACPI_CPU_HOTPLUG_H
> -
> -#include "hw/acpi/acpi.h"
> -#include "hw/acpi/pc-hotplug.h"
> -#include "hw/acpi/aml-build.h"
> -#include "hw/hotplug.h"
> -#include "hw/acpi/cpu.h"
> -
> -typedef struct AcpiCpuHotplug {
> -    Object *device;
> -    MemoryRegion io;
> -    uint8_t sts[ACPI_GPE_PROC_LEN];
> -} AcpiCpuHotplug;
> -
> -void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
> -                             AcpiCpuHotplug *g, DeviceState *dev, Error **errp);
> -
> -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> -                                  AcpiCpuHotplug *gpe_cpu, uint16_t base);
> -
> -void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu,
> -                                CPUHotplugState *cpuhp_state,
> -                                uint16_t io_port);
> -
> -void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine,
> -                                  uint16_t io_base);
> -#endif
> diff --git a/include/hw/acpi/ich9.h b/include/hw/acpi/ich9.h
> index 6a21472eb32e..019f0915c110 100644
> --- a/include/hw/acpi/ich9.h
> +++ b/include/hw/acpi/ich9.h
> @@ -22,12 +22,12 @@
>  #define HW_ACPI_ICH9_H
>  
>  #include "hw/acpi/acpi.h"
> -#include "hw/acpi/cpu_hotplug.h"
>  #include "hw/acpi/cpu.h"
>  #include "hw/acpi/pcihp.h"
>  #include "hw/acpi/memory_hotplug.h"
>  #include "hw/acpi/acpi_dev_interface.h"
>  #include "hw/acpi/ich9_tco.h"
> +#include "hw/acpi/cpu.h"
>  
>  #define ACPI_PCIHP_ADDR_ICH9 0x0cc0
>  
> diff --git a/include/hw/acpi/piix4.h b/include/hw/acpi/piix4.h
> index e075f0cbeaf1..863382a814ad 100644
> --- a/include/hw/acpi/piix4.h
> +++ b/include/hw/acpi/piix4.h
> @@ -24,11 +24,11 @@
>  
>  #include "hw/pci/pci_device.h"
>  #include "hw/acpi/acpi.h"
> -#include "hw/acpi/cpu_hotplug.h"
>  #include "hw/acpi/memory_hotplug.h"
>  #include "hw/acpi/pcihp.h"
>  #include "hw/i2c/pm_smbus.h"
>  #include "hw/isa/apm.h"
> +#include "hw/acpi/cpu.h"
>  
>  #define TYPE_PIIX4_PM "PIIX4_PM"
>  OBJECT_DECLARE_SIMPLE_TYPE(PIIX4PMState, PIIX4_PM)