Currently firmware uses 1 byte at 0x5F offset in RTC CMOS
to get number of CPUs present at boot. However 1 byte is
not enough to handle more than 255 CPUs. So add a fw_cfg
file that would allow QEMU to tell it.
For compat reasons add file only for machine types that
support more than 255 CPUs.
Signed-off-by: Igor Mammedov <imamm...@redhat.com>
---
hw/i386/pc.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 5fa5668..7161485 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -738,6 +738,7 @@ static void pc_build_smbios(FWCfgState *fw_cfg)
static FWCfgState *bochs_bios_init(AddressSpace *as, PCMachineState *pcms)
{
+ MachineClass *mc = MACHINE_GET_CLASS(pcms);
FWCfgState *fw_cfg;
uint64_t *numa_fw_cfg;
int i, j;
@@ -770,6 +771,11 @@ static FWCfgState *bochs_bios_init(AddressSpace *as,
PCMachineState *pcms)
sizeof(struct e820_entry) * e820_entries);
fw_cfg_add_bytes(fw_cfg, FW_CFG_HPET, &hpet_cfg, sizeof(hpet_cfg));
+ if (mc->max_cpus > 255) {
+ static uint16_t boot_cpus;
+ boot_cpus = cpu_to_le16(smp_cpus);
+ fw_cfg_add_file(fw_cfg, "etc/boot-cpus", &smp_cpus, sizeof(boot_cpus));
+ }
/* allocate memory for the NUMA channel: one (64bit) word for the number
* of nodes, one word for each VCPU->node and one word for each node to
* hold the amount of memory.
--
1.8.3.1
