Merge branch kvm-arm64/psci/cpu_on into kvmarm-master/next

PSCI fixes from Oliver Upton:
- Plug race on reset
- Ensure that a pending reset is applied before userspace accesses
- Reject PSCI requests with illegal affinity bits

* kvm-arm64/psci/cpu_on:
  selftests: KVM: Introduce psci_cpu_on_test
  KVM: arm64: Enforce reserved bits for PSCI target affinities
  KVM: arm64: Handle PSCI resets before userspace touches vCPU state
  KVM: arm64: Fix read-side race on updates to vcpu reset state

Signed-off-by: Marc Zyngier <maz@kernel.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index fd9a6bcf797f..1decdec70102 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1216,6 +1216,14 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		if (copy_from_user(&reg, argp, sizeof(reg)))
 			break;
 
+		/*
+		 * We could owe a reset due to PSCI. Handle the pending reset
+		 * here to ensure userspace register accesses are ordered after
+		 * the reset.
+		 */
+		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
+			kvm_reset_vcpu(vcpu);
+
 		if (ioctl == KVM_SET_ONE_REG)
 			r = kvm_arm_set_reg(vcpu, &reg);
 		else