Re: [RFC PATCH] kvm-unit-tests : Basic architecture of VMX nested test case

[Paolo Bonzini <pbonzini@redhat.com>]

Il 24/07/2013 08:11, Arthur Chunqi Li ha scritto:
> 
> static int vmx_run()
> {
>     u32 eax;
>     bool ret;
> 
>     vmcs_write(HOST_RSP, get_rsp());
>     ret = vmlaunch();

The compiler can still change rsp between here...

>     while (!ret) {
>         asm volatile(
>             "vmx_return:\n\t"

... and here.

If you want to write it in C, the only thing that can be after
vmlaunch/vmresume is "exit()".  Else it has to be asm.

Paolo

>             SAVE_GPR
>         );
>         eax = exit_handler();
>         switch (eax) {
>         case VMX_TEST_VMEXIT:
>             return 0;
>         case VMX_TEST_RESUME:
>             break;
>         default:
>             printf("%s : unhandled ret from exit_handler.\n", __func__);
>             return 1;
>         }
>         ret = vmresume();
>     }
>     printf("%s : vmenter failed.\n", __func__);
>     return 1;
> }