> On Jul 2, 2019, at 9:08 AM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 28/06/19 22:30, Nadav Amit wrote:
>> Enable to run the tests when test-device is not present (e.g.,
>> bare-metal). Users can provide the number of CPUs and ram size through
>> kernel parameters.
>>
>> On Ubuntu, for example, the tests can be run by copying a test to the
>> boot directory (/boot) and adding a menuentry to grub (editing
>> /etc/grub.d/40_custom):
>>
>> menuentry 'idt_test' {
>> set root='ROOT'
>> multiboot BOOT_RELATIVE/idt_test.flat ignore nb_cpus=48 \
>> ram_size=4294967296 no-test-device
>> }
>>
>> Replace ROOT with `grub-probe --target=bios_hints /boot` and
>> BOOT_RELATIVE with `grub-mkrelpath /boot`, and run update-grub.
>>
>> Note that the first kernel parameter is ignored for compatibility with
>> test executions through QEMU.
>>
>> Remember that the output goes to the serial port.
>
> RAM size can use the multiboot info (see lib/x86/setup.c).
The multiboot info, as provided by the boot-loader is not good enough as far
as I remember. The info just defines where to kernel can be loaded, but does
not say how big the memory is. For that, e820 decoding is needed, which I
was too lazy to do.
> For the # of CPUs I'm not sure what you're supposed to do on bare metal
> though. :)
I know you are not “serious”, but I’ll use this opportunity for a small
clarification. You do need to provide the real number of CPUs as otherwise
things will fail. I do not use cpuid, as my machine, for example has two
sockets. Decoding the ACPI tables is the right way, but I was too lazy to
implement it.
