[PATCH v2] KVM: arm64: Only set KVM_MODE_PROTECTED if is_hyp_mode_available()

[Marc Zyngier]

On Fri, 09 Sep 2022 18:55:18 +0100,
Elliot Berman <quic_eberman at quicinc.com> wrote:
> 
> 
> 
> On 9/9/2022 10:28 AM, Catalin Marinas wrote:
> > On Fri, Sep 09, 2022 at 07:45:52AM -0700, Elliot Berman wrote:
> >> Do not switch kvm_mode to KVM_MODE_PROTECTED if hypervisor mode is not
> >> available. This prevents "Protected KVM" cpu capability being reported
> >> when Linux is booting in EL1 and would not have KVM enabled.
> >> 
> >> Signed-off-by: Elliot Berman <quic_eberman at quicinc.com>
> >> ---
> >>   arch/arm64/kvm/arm.c | 4 +++-
> >>   1 file changed, 3 insertions(+), 1 deletion(-)
> >> 
> >> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> >> index 8fe73ee5fa84..861f4b388879 100644
> >> --- a/arch/arm64/kvm/arm.c
> >> +++ b/arch/arm64/kvm/arm.c
> >> @@ -2272,7 +2272,9 @@ static int __init early_kvm_mode_cfg(char *arg)
> >>   		return -EINVAL;
> >>     	if (strcmp(arg, "protected") == 0) {
> >> -		if (!is_kernel_in_hyp_mode())
> >> +		if (!is_hyp_mode_available())
> >> +			kvm_mode = KVM_MODE_DEFAULT;
> > 
> > I think kvm_mode is already KVM_MODE_DEFAULT at this point. You may want
> > to print a warning instead.
> > 
> 
> Does it make sense to print warning for kvm-arm.mode=nvhe as well?

In general, specifying a kvm-arm.mode when no hypervisor mode is
available should be reported as a warning.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.