diff --git a/lib/psci/psci_main.c b/lib/psci/psci_main.c index 4105e63bd..8e41cf026 100644 --- a/lib/psci/psci_main.c +++ b/lib/psci/psci_main.c @@ -220,6 +220,23 @@ int psci_affinity_info(u_register_t target_affinity, if (target_idx == -1) return PSCI_E_INVALID_PARAMS; + /* + * Generic management: + * Perform cache maintanence ahead of reading the target CPU state to + * ensure that the data is not stale. + * There is a theoretical edge case where the cache may contain stale + * data for the target CPU data - this can occur under the following + * conditions: + * - the target CPU is in another cluster from the current + * - the target CPU was the last CPU to shutdown on its cluster + * - the cluster was removed from coherency as part of the CPU shutdown + * + * In this case the cache maintenace that was performed as part of the + * target CPUs shutdown was not seen by the current CPU's cluster. And + * so the cache may contain stale data for the target CPU. + */ + flush_cpu_data_by_index(target_idx, psci_svc_cpu_data.aff_info_state); + return psci_get_aff_info_state_by_idx(target_idx); }