| From | Steven Price <> | Subject | [RFC PATCH 22/28] arm64: Don't expose stolen time for realm guests | Date | Fri, 27 Jan 2023 11:29:26 +0000 |
| |
It doesn't make much sense and with the ABI as it is it's a footgun for the VMM which makes fatal granule protection faults easy to trigger.
Signed-off-by: Steven Price <steven.price@arm.com> --- arch/arm64/kvm/arm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 46c152a9a150..645df5968e1e 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -302,7 +302,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = system_supports_mte(); break; case KVM_CAP_STEAL_TIME: - r = kvm_arm_pvtime_supported(); + if (kvm && kvm_is_realm(kvm)) + r = 0; + else + r = kvm_arm_pvtime_supported(); break; case KVM_CAP_ARM_EL1_32BIT: r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); -- 2.34.1
|