4.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> commit e2d997366dc5b6c9d14035867f73957f93e7578c upstream. According to the PSCI specification and the SMC/HVC calling convention, PSCI function_ids that are not implemented must return NOT_SUPPORTED as return value. Current KVM implementation takes an unhandled PSCI function_id as an error and injects an undefined instruction into the guest if PSCI implementation is called with a function_id that is not handled by the resident PSCI version (ie it is not implemented), which is not the behaviour expected by a guest when calling a PSCI function_id that is not implemented. This patch fixes this issue by returning NOT_SUPPORTED whenever the kvm PSCI call is executed for a function_id that is not implemented by the PSCI kvm layer. Cc: Christoffer Dall <christoffer.dall@xxxxxxxxxx> Acked-by: Sudeep Holla <sudeep.holla@xxxxxxx> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm/kvm/psci.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -230,10 +230,6 @@ static int kvm_psci_0_2_call(struct kvm_ case PSCI_0_2_FN64_AFFINITY_INFO: val = kvm_psci_vcpu_affinity_info(vcpu); break; - case PSCI_0_2_FN_MIGRATE: - case PSCI_0_2_FN64_MIGRATE: - val = PSCI_RET_NOT_SUPPORTED; - break; case PSCI_0_2_FN_MIGRATE_INFO_TYPE: /* * Trusted OS is MP hence does not require migration @@ -242,10 +238,6 @@ static int kvm_psci_0_2_call(struct kvm_ */ val = PSCI_0_2_TOS_MP; break; - case PSCI_0_2_FN_MIGRATE_INFO_UP_CPU: - case PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU: - val = PSCI_RET_NOT_SUPPORTED; - break; case PSCI_0_2_FN_SYSTEM_OFF: kvm_psci_system_off(vcpu); /* @@ -271,7 +263,8 @@ static int kvm_psci_0_2_call(struct kvm_ ret = 0; break; default: - return -EINVAL; + val = PSCI_RET_NOT_SUPPORTED; + break; } *vcpu_reg(vcpu, 0) = val; @@ -291,12 +284,9 @@ static int kvm_psci_0_1_call(struct kvm_ case KVM_PSCI_FN_CPU_ON: val = kvm_psci_vcpu_on(vcpu); break; - case KVM_PSCI_FN_CPU_SUSPEND: - case KVM_PSCI_FN_MIGRATE: + default: val = PSCI_RET_NOT_SUPPORTED; break; - default: - return -EINVAL; } *vcpu_reg(vcpu, 0) = val; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html