get_wave_state acquires the mmap_lock on copy_to_user but so do mmu_notifiers. mmu_notifiers allows dqm locking so do get_wave_state outside the dqm_lock to prevent circular locking.
Signed-off-by: Jonathan Kim <[email protected]> Reviewed-by: Felix Kuehling <[email protected]> --- .../drm/amd/amdkfd/kfd_device_queue_manager.c | 27 +++++++++---------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c index edb14e4a9f33..e6366b408420 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c @@ -1678,25 +1678,24 @@ static int get_wave_state(struct device_queue_manager *dqm, dqm_lock(dqm); - if (q->properties.type != KFD_QUEUE_TYPE_COMPUTE || - q->properties.is_active || !q->device->cwsr_enabled) { - r = -EINVAL; - goto dqm_unlock; - } - mqd_mgr = dqm->mqd_mgrs[KFD_MQD_TYPE_CP]; - if (!mqd_mgr->get_wave_state) { - r = -EINVAL; - goto dqm_unlock; + if (q->properties.type != KFD_QUEUE_TYPE_COMPUTE || + q->properties.is_active || !q->device->cwsr_enabled || + !mqd_mgr->get_wave_state) { + dqm_unlock(dqm); + return -EINVAL; } - r = mqd_mgr->get_wave_state(mqd_mgr, q->mqd, ctl_stack, - ctl_stack_used_size, save_area_used_size); - -dqm_unlock: dqm_unlock(dqm); - return r; + + /* + * get_wave_state is outside the dqm lock to prevent circular locking + * and the queue should be protected against destruction by the process + * lock. + */ + return mqd_mgr->get_wave_state(mqd_mgr, q->mqd, ctl_stack, + ctl_stack_used_size, save_area_used_size); } static int process_termination_cpsch(struct device_queue_manager *dqm, -- 2.25.1 _______________________________________________ amd-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/amd-gfx
