From 5ff020b7b02dce36a66c106df986ff68f8452542 Mon Sep 17 00:00:00 2001 From: Eduardo Habkost Date: Fri, 14 Mar 2014 16:33:51 -0300 Subject: pc: Refuse CPU hotplug if the resulting APIC ID is too large The ACPI CPU hotplug code requires APIC IDs to be smaller than ACPI_CPU_HOTPLUG_ID_LIMIT, so enforce the limit before trying to hotplug a new vCPU, returning an error instead of crashing. Signed-off-by: Eduardo Habkost Reviewed-by: Laszlo Ersek Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/pc.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'hw/i386/pc.c') diff --git a/hw/i386/pc.c b/hw/i386/pc.c index e715a3312d..74cb4f962c 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -53,6 +53,7 @@ #include "qemu/bitmap.h" #include "qemu/config-file.h" #include "hw/acpi/acpi.h" +#include "hw/acpi/cpu_hotplug.h" #include "hw/cpu/icc_bus.h" #include "hw/boards.h" #include "hw/pci/pci_host.h" @@ -974,6 +975,13 @@ void pc_hot_add_cpu(const int64_t id, Error **errp) return; } + if (apic_id >= ACPI_CPU_HOTPLUG_ID_LIMIT) { + error_setg(errp, "Unable to add CPU: %" PRIi64 + ", resulting APIC ID (%" PRIi64 ") is too large", + id, apic_id); + return; + } + icc_bridge = DEVICE(object_resolve_path_type("icc-bridge", TYPE_ICC_BRIDGE, NULL)); pc_new_cpu(current_cpu_model, apic_id, icc_bridge, errp); -- cgit 1.4.1 From f03bd716a2935532379cff1c71c6f0f399921b70 Mon Sep 17 00:00:00 2001 From: Eduardo Habkost Date: Fri, 14 Mar 2014 16:33:54 -0300 Subject: pc: Refuse max_cpus if it results in too large APIC ID This changes the PC initialization code to reject max_cpus if it results in an APIC ID that's too large, instead of aborting or erroring out when it is already too late. Signed-off-by: Eduardo Habkost Reviewed-by: Laszlo Ersek Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/pc.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'hw/i386/pc.c') diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 74cb4f962c..14f0d91f76 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -992,6 +992,7 @@ void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge) int i; X86CPU *cpu = NULL; Error *error = NULL; + unsigned long apic_id_limit; /* init CPUs */ if (cpu_model == NULL) { @@ -1003,6 +1004,13 @@ void pc_cpus_init(const char *cpu_model, DeviceState *icc_bridge) } current_cpu_model = cpu_model; + apic_id_limit = pc_apic_id_limit(max_cpus); + if (apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { + error_report("max_cpus is too large. APIC ID of last CPU is %lu", + apic_id_limit - 1); + exit(1); + } + for (i = 0; i < smp_cpus; i++) { cpu = pc_new_cpu(cpu_model, x86_cpu_apic_id_from_index(i), icc_bridge, &error); -- cgit 1.4.1