Re: [PATCH v3 06/10] hvf: Add Apple Silicon support

[Roman Bolshakov]

On Wed, Dec 02, 2020 at 08:04:04PM +0100, Alexander Graf wrote:
> With Apple Silicon available to the masses, it's a good time to add support
> for driving its virtualization extensions from QEMU.
> 
> This patch adds all necessary architecture specific code to get basic VMs
> working. It's still pretty raw, but definitely functional.
> 

That's very cool, Alex!

>
> [...]
> diff --git a/accel/hvf/hvf-cpus.c b/accel/hvf/hvf-cpus.c
> index a423f629d5..e613c22ad0 100644
> --- a/accel/hvf/hvf-cpus.c
> +++ b/accel/hvf/hvf-cpus.c
> @@ -60,6 +60,10 @@
>  
>  #include <Hypervisor/Hypervisor.h>
>  

On an older laptop with 10.15 I've noticed this causes a build failure.
Here's layout of Hypervisor.framework on 10.15:

 Hypervisor.framework find .
 .
 ./Versions
 ./Versions/A
 ./Versions/A/Hypervisor.tbd
 ./Versions/A/Headers
 ./Versions/A/Headers/hv_arch_vmx.h
 ./Versions/A/Headers/hv_error.h
 ./Versions/A/Headers/hv_types.h
 ./Versions/A/Headers/hv.h
 ./Versions/A/Headers/hv_arch_x86.h
 ./Versions/A/Headers/hv_vmx.h
 ./Versions/Current
 ./module.map
 ./Hypervisor.tbd
 ./Headers

The issue also exists in another patch in the series:
  "hvf: Move common code out"

> +#ifdef __aarch64__
> +#define HV_VM_DEFAULT NULL
> +#endif
> +

I don't see if it's used anywhere.

>  /* Memory slots */
>  
>  struct mac_slot {
> [...]
>

Side question. I have very little knowledge of ARM but it seems much
leaner compared to x86 trap/emulation layer. Is it a consequence of
load/store architecture and it's expected to be that small on ARM?

I have only noticed MMIO, system registers (access to them apparently
leads to a trap), kick and PSCI traps (which sounds somewhat similar to
Intel MPSpec/APIC) and no system instruction traps (except WFI in the
next patch).

Thanks,
Roman