drm/amdkfd: Fix incorrect use of process->mm

This mm_struct pointer should never be dereferenced. If running in
a user thread, just use current->mm. If running in a kernel worker
use get_task_mm to get a safe reference to the mm_struct.

Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Felix Kuehling 2018-10-02 18:41:12 -04:00 committed by Alex Deucher
parent 987bf11644
commit 11b29c9e25

View File

@ -358,8 +358,8 @@ static int create_compute_queue_nocpsch(struct device_queue_manager *dqm,
struct queue *q,
struct qcm_process_device *qpd)
{
int retval;
struct mqd_manager *mqd_mgr;
int retval;
mqd_mgr = dqm->ops.get_mqd_manager(dqm, KFD_MQD_TYPE_COMPUTE);
if (!mqd_mgr)
@ -387,8 +387,12 @@ static int create_compute_queue_nocpsch(struct device_queue_manager *dqm,
if (!q->properties.is_active)
return 0;
retval = mqd_mgr->load_mqd(mqd_mgr, q->mqd, q->pipe, q->queue,
&q->properties, q->process->mm);
if (WARN(q->process->mm != current->mm,
"should only run in user thread"))
retval = -EFAULT;
else
retval = mqd_mgr->load_mqd(mqd_mgr, q->mqd, q->pipe, q->queue,
&q->properties, current->mm);
if (retval)
goto out_uninit_mqd;
@ -545,9 +549,15 @@ static int update_queue(struct device_queue_manager *dqm, struct queue *q)
retval = map_queues_cpsch(dqm);
else if (q->properties.is_active &&
(q->properties.type == KFD_QUEUE_TYPE_COMPUTE ||
q->properties.type == KFD_QUEUE_TYPE_SDMA))
retval = mqd_mgr->load_mqd(mqd_mgr, q->mqd, q->pipe, q->queue,
&q->properties, q->process->mm);
q->properties.type == KFD_QUEUE_TYPE_SDMA)) {
if (WARN(q->process->mm != current->mm,
"should only run in user thread"))
retval = -EFAULT;
else
retval = mqd_mgr->load_mqd(mqd_mgr, q->mqd,
q->pipe, q->queue,
&q->properties, current->mm);
}
out_unlock:
dqm_unlock(dqm);
@ -653,6 +663,7 @@ static int evict_process_queues_cpsch(struct device_queue_manager *dqm,
static int restore_process_queues_nocpsch(struct device_queue_manager *dqm,
struct qcm_process_device *qpd)
{
struct mm_struct *mm = NULL;
struct queue *q;
struct mqd_manager *mqd_mgr;
struct kfd_process_device *pdd;
@ -686,6 +697,15 @@ static int restore_process_queues_nocpsch(struct device_queue_manager *dqm,
kfd_flush_tlb(pdd);
}
/* Take a safe reference to the mm_struct, which may otherwise
* disappear even while the kfd_process is still referenced.
*/
mm = get_task_mm(pdd->process->lead_thread);
if (!mm) {
retval = -EFAULT;
goto out;
}
/* activate all active queues on the qpd */
list_for_each_entry(q, &qpd->queues_list, list) {
if (!q->properties.is_evicted)
@ -700,14 +720,15 @@ static int restore_process_queues_nocpsch(struct device_queue_manager *dqm,
q->properties.is_evicted = false;
q->properties.is_active = true;
retval = mqd_mgr->load_mqd(mqd_mgr, q->mqd, q->pipe,
q->queue, &q->properties,
q->process->mm);
q->queue, &q->properties, mm);
if (retval)
goto out;
dqm->queue_count++;
}
qpd->evicted = 0;
out:
if (mm)
mmput(mm);
dqm_unlock(dqm);
return retval;
}