Commit 63f6e012 authored by Jonathan Kim's avatar Jonathan Kim Committed by Alex Deucher
Browse files

drm/amdkfd: fix circular locking on get_wave_state 



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.

v2: squash in unused variable removal.

Signed-off-by: default avatarJonathan Kim <jonathan.kim@amd.com>
Reviewed-by: default avatarFelix Kuehling <felix.kuehling@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 03fc4cf4

drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c

+13 −15
Original line number Diff line number Diff line
@@ -1674,29 +1674,27 @@ static int get_wave_state(struct device_queue_manager *dqm, 
			  u32 *save_area_used_size)

{

	struct mqd_manager *mqd_mgr;

	int r;



	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,