KVM: arm64: Ignore kvm-arm.mode if !is_hyp_mode_available()

Ignore kvm-arm.mode if !is_hyp_mode_available(). Specifically, we want
to avoid switching 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.
Reasonably though, we should warn if the command line is requesting a
KVM mode at all if KVM isn't actually available. Allow
"kvm-arm.mode=none" to skip the warning since this would disable KVM
anyway.

Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220920190658.2880184-1-quic_eberman@quicinc.com
This commit is contained in:
Elliot Berman
2022-09-20 12:06:58 -07:00
committed by Marc Zyngier
parent 096560dd13
commit b2a4d007c3

View File

@@ -2270,6 +2270,16 @@ static int __init early_kvm_mode_cfg(char *arg)
if (!arg)
return -EINVAL;
if (strcmp(arg, "none") == 0) {
kvm_mode = KVM_MODE_NONE;
return 0;
}
if (!is_hyp_mode_available()) {
pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
return 0;
}
if (strcmp(arg, "protected") == 0) {
if (!is_kernel_in_hyp_mode())
kvm_mode = KVM_MODE_PROTECTED;
@@ -2284,11 +2294,6 @@ static int __init early_kvm_mode_cfg(char *arg)
return 0;
}
if (strcmp(arg, "none") == 0) {
kvm_mode = KVM_MODE_NONE;
return 0;
}
return -EINVAL;
}
early_param("kvm-arm.mode", early_kvm_mode_cfg);