On Sun, Jul 25, 2021, Robert Hoo wrote:
> PML in VM depends on "enable PML" in VM-execution control, check this
> before vmwrite to PMLADDR, because this field doesn't exist if PML is
> disabled in VM-execution control.
No, the field doesn't exist if the CPU doesn't support PML. Whether or not PML
is enabled in the execution controls is irrelevant. pml_init() checks for both
secondary execution controls and PML support (with bad indentation).
if (!(ctrl_cpu_rev[0].clr & CPU_SECONDARY) ||
!(ctrl_cpu_rev[1].clr & CPU_PML)) {
printf("\tPML is not supported");
return VMX_TEST_EXIT;
}
pml_log = alloc_page();
vmcs_write(PMLADDR, (u64)pml_log);
vmcs_write(GUEST_PML_INDEX, PML_INDEX - 1);
> Signed-off-by: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>
> ---
> x86/vmx_tests.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
> index 4f712eb..8663112 100644
> --- a/x86/vmx_tests.c
> +++ b/x86/vmx_tests.c
> @@ -1502,13 +1502,16 @@ static int pml_init(struct vmcs *vmcs)
> return VMX_TEST_EXIT;
> }
>
> + ctrl_cpu = vmcs_read(CPU_EXEC_CTRL1) & CPU_PML;
> + if (!ctrl_cpu) {
> + printf("\tPML is not enabled\n");
> + return VMX_TEST_EXIT;
> + }
> +
> pml_log = alloc_page();
> vmcs_write(PMLADDR, (u64)pml_log);
> vmcs_write(GUEST_PML_INDEX, PML_INDEX - 1);
>
> - ctrl_cpu = vmcs_read(CPU_EXEC_CTRL1) | CPU_PML;
> - vmcs_write(CPU_EXEC_CTRL1, ctrl_cpu);
> -
> return VMX_TEST_START;
> }
>
> --
> 1.8.3.1
>
