Commit e3cadac0 authored by Igor Mammedov's avatar Igor Mammedov Committed by Eduardo Habkost
Browse files

pc: fix FW_CFG_NB_CPUS to account for -device added CPUs 



Signed-off-by: default avatarIgor Mammedov <imammedo@redhat.com>
Message-Id: <1479301481-197333-1-git-send-email-imammedo@redhat.com>
Reviewed-by: default avatarEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
parent 5836d168

hw/i386/pc.c

+27 −17
Original line number Diff line number Diff line
@@ -744,7 +744,7 @@ static FWCfgState *bochs_bios_init(AddressSpace *as, PCMachineState *pcms) 
    int i, j;



    fw_cfg = fw_cfg_init_io_dma(FW_CFG_IO_BASE, FW_CFG_IO_BASE + 4, as);

    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)smp_cpus);

    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, pcms->boot_cpus);



    /* FW_CFG_MAX_CPUS is a bit confusing/problematic on x86:

     *
@@ -1087,17 +1087,6 @@ void pc_acpi_smi_interrupt(void *opaque, int irq, int level) 
    }

}



static int pc_present_cpus_count(PCMachineState *pcms)

{

    int i, boot_cpus = 0;

    for (i = 0; i < pcms->possible_cpus->len; i++) {

        if (pcms->possible_cpus->cpus[i].cpu) {

            boot_cpus++;

        }

    }

    return boot_cpus;

}



static X86CPU *pc_new_cpu(const char *typename, int64_t apic_id,

                          Error **errp)

{
@@ -1234,6 +1223,19 @@ static void pc_build_feature_control_file(PCMachineState *pcms) 
    fw_cfg_add_file(pcms->fw_cfg, "etc/msr_feature_control", val, sizeof(*val));

}



static void 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

void pc_machine_done(Notifier *notifier, void *data)

{
@@ -1242,7 +1244,7 @@ void pc_machine_done(Notifier *notifier, void *data) 
    PCIBus *bus = pcms->bus;



    /* set the number of CPUs */

    rtc_set_memory(pcms->rtc, 0x5f, pc_present_cpus_count(pcms) - 1);

    rtc_set_cpus_count(pcms->rtc, pcms->boot_cpus);



    if (bus) {

        int extra_hosts = 0;
@@ -1265,6 +1267,8 @@ void pc_machine_done(Notifier *notifier, void *data) 
    if (pcms->fw_cfg) {

        pc_build_smbios(pcms->fw_cfg);

        pc_build_feature_control_file(pcms);

        /* update FW_CFG_NB_CPUS to account for -device added CPUs */

        fw_cfg_modify_i16(pcms->fw_cfg, FW_CFG_NB_CPUS, pcms->boot_cpus);

    }



    if (pcms->apic_id_limit > 255) {
@@ -1342,7 +1346,7 @@ void xen_load_linux(PCMachineState *pcms) 
    assert(MACHINE(pcms)->kernel_filename != NULL);



    fw_cfg = fw_cfg_init_io(FW_CFG_IO_BASE);

    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, (uint16_t)smp_cpus);

    fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, pcms->boot_cpus);

    rom_set_fw(fw_cfg);



    load_linux(pcms, fw_cfg);
@@ -1812,9 +1816,11 @@ static void pc_cpu_plug(HotplugHandler *hotplug_dev, 
        }

    }



    if (dev->hotplugged) {

    /* increment the number of CPUs */

        rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) + 1);

    pcms->boot_cpus++;

    if (dev->hotplugged) {

        rtc_set_cpus_count(pcms->rtc, pcms->boot_cpus);

        fw_cfg_modify_i16(pcms->fw_cfg, FW_CFG_NB_CPUS, pcms->boot_cpus);

    }



    found_cpu = pc_find_cpu_slot(pcms, CPU(dev), NULL);
@@ -1868,7 +1874,11 @@ static void pc_cpu_unplug_cb(HotplugHandler *hotplug_dev, 
    found_cpu->cpu = NULL;

    object_unparent(OBJECT(dev));



    rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) - 1);

    /* decrement the number of CPUs */

    pcms->boot_cpus--;

    /* Update the number of CPUs in CMOS */

    rtc_set_cpus_count(pcms->rtc, pcms->boot_cpus);

    fw_cfg_modify_i16(pcms->fw_cfg, FW_CFG_NB_CPUS, pcms->boot_cpus);

 out:

    error_propagate(errp, local_err);

}

include/hw/i386/pc.h

+2 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
/**

 * PCMachineState:

 * @acpi_dev: link to ACPI PM device that performs ACPI hotplug handling

 * @boot_cpus: number of present VCPUs

 */

struct PCMachineState {

    /*< private >*/
@@ -70,6 +71,7 @@ struct PCMachineState { 
    bool apic_xrupt_override;

    unsigned apic_id_limit;

    CPUArchIdList *possible_cpus;

    uint16_t boot_cpus;



    /* NUMA information: */

    uint64_t numa_nodes;