Nova on a bit old CPU

[Paul Dufresne]

I have realized that if I set the CPU to coreDuo in QEMU rather than 
core2Duo, my run/bomb
program would not give any output at all.

My real CPU is a dual core. But the BIOS does not enable virtualization 
per default.
I believe I have a CPU with vmx flag, that does not have IOMMU 
(dmidecode does not show
a DMAR (DMA relocalistion) table).

Here is my /proc/cpuinfo:
processor    : 0
vendor_id    : GenuineIntel
cpu family    : 6
model        : 15
model name    : Intel(R) Core(TM)2 CPU          6300  @ 1.86GHz
stepping    : 6
microcode    : 0xd0
cpu MHz        : 1821.338
cache size    : 2048 KB
physical id    : 0
siblings    : 2
core id        : 0
cpu cores    : 2
apicid        : 0
initial apicid    : 0
fpu        : yes
fpu_exception    : yes
cpuid level    : 10
wp        : yes
flags        : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca 
cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall 
nx lm constant_tsc arch_perfmon pebs bts nopl cpuid aperfmperf pni 
dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm pti 
tpr_shadow dtherm
bugs        : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass
bogomips    : 3721.03
clflush size    : 64
cache_alignment    : 64
address sizes    : 36 bits physical, 48 bits virtual
power management:

I had the idea to test run/bomb in QEMU with my host CPU, but after 
installing a KVM linux kernel,
it was not booting (if BIOS have virtualization enabled, would hang on 
loading boot image kind
of message).

I do remember that a few years ago, the author of Nova, had it modified 
so that it booted on
my Pentium 4. But I guess something went wrong with the years. He sure 
did not really happy
back then to know that people where still using CPU that does not 
support IOMMU.

I tried with Pentium3 emulation and QEMU after 3 to 5 mins, said that 
the program had try to
write outside memory, and that it probably means I was running an image 
not compatible with
my machine.

Now, I suppose that the fact QEMU cannot handle some older CPUs on Nova 
well...
that there is some way to debug it in an easier way than on real hardware?
I am still trying to figure how ... however.