[PATCH] KVM: arm64: Report Protected KVM cap only if KVM is enabled

From: Elliot Berman
Date: Fri Sep 02 2022 - 00:02:11 EST


If "kvm-arm.mode=protected" is present on kernel command line, but the
kernel doesn't actually support KVM because it booted from EL1, the
ARM64_KVM_PROTECTED_MODE capability is misleadingly reported as present.
Fix this by adding a check whether we booted from EL2.

Cc: Will Deacon <will@xxxxxxxxxx>
Cc: David Brazdil <dbrazdil@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 8d88433de81d..866667be0651 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1974,7 +1974,7 @@ static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
#ifdef CONFIG_KVM
static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
{
- return kvm_get_mode() == KVM_MODE_PROTECTED;
+ return is_hyp_mode_available() && kvm_get_mode() == KVM_MODE_PROTECTED;
}
#endif /* CONFIG_KVM */


base-commit: 0982c8d859f8f7022b9fd44d421c7ec721bb41f9
--
2.25.1