Re: [kvm-unit-tests PATCH 3/3] x86: Support environments without test-devices

[Nadav Amit <nadav.amit@gmail.com>]

> On Jul 15, 2019, at 8:48 AM, Andrew Jones <drjones@redhat.com> wrote:
> 
> On Fri, Jun 28, 2019 at 01:30:19PM -0700, 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.
> 
> Can you provide multiboot a pointer to an initrd (text file) with
> environment variables listed instead? Because this works
> 
> $ cat x86/params.c 
> #include <libcflat.h>
> int main(void)
> {
>    printf("nr_cpus=%ld\n", atol(getenv("NR_CPUS")));
>    printf("memsize=%ld\n", atol(getenv("MEMSIZE")));
>    return 0;
> }
> 
> $ cat params.initrd 
> NR_CPUS=2
> MEMSIZE=256
> 
> $ qemu-system-x86_64 -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel x86/params.flat -initrd params.initrd
> enabling apic
> enabling apic
> nr_cpus=2
> memsize=256
> 
> 
> This works because setup_multiboot() looks for an initrd, and then,
> if present, it gets interpreted as a list of environment variables
> which become the unit tests **envp.

Looks like a nice solution, but Paolo preferred to see if this information
can be extracted from e810 and ACPI MADT. Paolo?