Merge branch 'for-next/cpufeature' into for-next/core

Additional CPU sanity checks for MTE and preparatory changes for systems
where not all of the CPUs support 32-bit EL0.

* for-next/cpufeature:
  arm64: Restrict undef hook for cpufeature registers
  arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs
  KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support
  arm64: Allow mismatched 32-bit EL0 support
  arm64: cpuinfo: Split AArch32 registers out into a separate struct
  arm64: Check if GMID_EL1.BS is the same on all CPUs
  arm64: Change the cpuinfo_arm64 member type for some sysregs to u64

1 files changed, 10 insertions, 1 deletions

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index c1953f65ca0e..dc2bc5589493 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -692,6 +692,15 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu)
 	}
 }
 
+static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
+{
+	if (likely(!vcpu_mode_is_32bit(vcpu)))
+		return false;
+
+	return !system_supports_32bit_el0() ||
+		static_branch_unlikely(&arm64_mismatched_32bit_el0);
+}
+
 /**
  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
  * @vcpu:	The VCPU pointer
@@ -875,7 +884,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		 * with the asymmetric AArch32 case), return to userspace with
 		 * a fatal error.
 		 */
-		if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) {
+		if (vcpu_mode_is_bad_32bit(vcpu)) {
 			/*
 			 * As we have caught the guest red-handed, decide that
 			 * it isn't fit for purpose anymore by making the vcpu