FROMGIT: 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

Bug: 249052880
(cherry picked from commit b2a4d007c347b4cb4c60f7512733c3f8300a129c
 https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git next)
Change-Id: I196649fc00537e563a1fab0a22bf23c5b7abe00d
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
(cherry picked from commit 8015dd49c00e036b214801b34a727b7c98aa84e3)
This commit is contained in:
Elliot Berman
2022-09-20 12:06:58 -07:00
committed by Treehugger Robot
parent dbcd8cb535
commit 9a1be9a472

View File

@@ -2142,6 +2142,16 @@ 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) {
kvm_mode = KVM_MODE_PROTECTED;
return 0;
@@ -2152,11 +2162,6 @@ 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);