On 2024-11-28 11:26, Andrew Martin wrote:
> In the function pqm_uninit there is a call-assignment of "pdd =
> kfd_get_process_device_data" which could be null, and this value was
> later dereferenced without checking.
>
> Signed-off-by: Andrew Martin <Andrew.Martin@xxxxxxx>
This seems to fix a bug introduced by a previous patch. Please add a Fixes tag for that:
Fixes: fb91065851cd ("drm/amdkfd: Refactor queue wptr_bo GART mapping")
> ---
> .../drm/amd/amdkfd/kfd_process_queue_manager.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> index c76db22a1000..808c447879c0 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> @@ -212,13 +212,21 @@ static void pqm_clean_queue_resource(struct process_queue_manager *pqm,
> void pqm_uninit(struct process_queue_manager *pqm)
> {
> struct process_queue_node *pqn, *next;
> - struct kfd_process_device *pdd;
>
> list_for_each_entry_safe(pqn, next, &pqm->queues, process_queue_list) {
> if (pqn->q) {
> - pdd = kfd_get_process_device_data(pqn->q->device, pqm->process);
> - kfd_queue_unref_bo_vas(pdd, &pqn->q->properties);
> - kfd_queue_release_buffers(pdd, &pqn->q->properties);
> + struct kfd_process_device *pdd =
> + kfd_get_process_device_data(
> + pqn->q->device,
> + pqm->process);
> + if (pdd) {
checkpatch.pl will complain without an empty line after the variable declaration.
> + kfd_queue_unref_bo_vas(
> + pdd,
> + &pqn->q->properties);
> + kfd_queue_release_buffers(
> + pdd,
> + &pqn->q->properties);
> + }
I think it should be impossible for pdd to be NULL here. Without a PDD, the queue could not have been created in the first place. If we want to add a NULL check here, we should make that a WARN or WARN_ON because it would indicate some serious bug somewhere. The result would be a memory leak here, so we need to warn about that.
Regards,
Felix
> pqm_clean_queue_resource(pqm, pqn);
> }
>
