Re: kvm guest for 486 sx

[Gleb Natapov <gleb@redhat.com>]

On Tue, Jul 07, 2009 at 08:06:10AM -0400, Jerry Geis wrote:
> Avi Kivity wrote:
>> On 07/06/2009 10:58 PM, Jerry Geis wrote:
>>> I wish to run as a guest a 486 SX equivalent
>>> is there an option to disable the floating point support?
>>>
>>> Is it possible to do this?
>>>
>>
>> Try -cpu 486,-fpu.
>>
> Avi,
>
> Running this command:
> qemu-system-x86_64 -net nic,model=rtl8139 -net user -hda $1 -no-acpi  
> -usb -cpu 486,-fpu &
>
> I get a seg fault:
> qemu-system-x86[15419]: segfault at c ip 0000000000458b95 sp  
> 0000000041d9df90 error 4 in qemu-system-x86_64[400000+208000]
>
>
> I am running kvm-87 centos 5.3 x86_64.
>
Apply the patch and try again please.


diff --git a/hw/apic.c b/hw/apic.c
index 778a853..3e79377 100644
--- a/hw/apic.c
+++ b/hw/apic.c
@@ -955,7 +955,8 @@ static void kvm_kernel_lapic_load_from_user(APICState *s)
 void qemu_kvm_load_lapic(CPUState *env)
 {
 #ifdef KVM_CAP_IRQCHIP
-    if (kvm_enabled() && kvm_vcpu_inited(env) && qemu_kvm_irqchip_in_kernel()) {
+    if (kvm_enabled() && kvm_vcpu_inited(env) &&
+		    qemu_kvm_irqchip_in_kernel() && env->apic_state) {
         kvm_kernel_lapic_load_from_user(env->apic_state);
     }
 #endif
--
			Gleb.