[RFC,04/14] pc: leave max apic_id_limit only in legacy cpu hotplug code

Commit Message

Igor Mammedov May 9, 2016, 9:26 a.m. UTC

that's enough to make old code that depends on it
to prevent QEMU starting with more than 255 CPUs.

Signed-off-by: Igor Mammedov <[e-mail]>
---
 hw/acpi/cpu_hotplug.c | 7 ++++++-
 hw/i386/pc.c          | 7 -------
 2 files changed, 6 insertions(+), 8 deletions(-)

Patch

diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c
index 6c0b555..bd8d915 100644
--- a/hw/acpi/cpu_hotplug.c
+++ b/hw/acpi/cpu_hotplug.c
@@ -15,6 +15,7 @@ 
 #include "qapi/error.h"
 #include "qom/cpu.h"
 #include "hw/i386/pc.h"
+#include "qemu/error-report.h"
 
 #define CPU_EJECT_METHOD "CPEJ"
 #define CPU_MAT_METHOD "CPMA"
@@ -215,7 +216,11 @@  void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine,
     /* 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);
-    g_assert(pcms->apic_id_limit <= ACPI_CPU_HOTPLUG_ID_LIMIT);
+    if (pcms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) {
+        error_report("max_cpus is too large. APIC ID of last CPU is %u",
+                     pcms->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));
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 7072fb5..1baf01b 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -780,7 +780,6 @@  static FWCfgState *bochs_bios_init(AddressSpace *as, PCMachineState *pcms)
     numa_fw_cfg[0] = cpu_to_le64(nb_numa_nodes);
     for (i = 0; i < max_cpus; i++) {
         unsigned int apic_id = x86_cpu_apic_id_from_index(i);
-        assert(apic_id < pcms->apic_id_limit);
         for (j = 0; j < nb_numa_nodes; j++) {
             if (test_bit(i, numa_info[j].node_cpu)) {
                 numa_fw_cfg[apic_id + 1] = cpu_to_le64(j);
@@ -1133,12 +1132,6 @@  void pc_cpus_init(PCMachineState *pcms)
      * This is used for FW_CFG_MAX_CPUS. See comments on bochs_bios_init().
      */
     pcms->apic_id_limit = x86_cpu_apic_id_from_index(max_cpus - 1) + 1;
-    if (pcms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) {
-        error_report("max_cpus is too large. APIC ID of last CPU is %u",
-                     pcms->apic_id_limit - 1);
-        exit(1);
-    }
-
     pcms->possible_cpus = g_malloc0(sizeof(CPUArchIdList) +
                                     sizeof(CPUArchId) * max_cpus);
     pcms->node_cpu = g_malloc0(max_cpus * sizeof *pcms->node_cpu);