From the comments , "we will loop GPUs that already be processed (with lower value of proximity_domain) ", the device should already been added into the topology_device_list. So in this case , kfd_topology_device_by_proximity_domain will not return a NULL pointer. If you really get the null pointer dereferences here , we must have some bigger problem and can not solved by added the null check here. Regards shaoyun.liu On 2019-06-29 9:31 a.m., Colin King wrote: > From: Colin Ian King <colin.king@xxxxxxxxxxxxx> > > The call to kfd_topology_device_by_proximity_domain can return a NULL > pointer so add a null pointer check on peer_dev to the existing null > pointer check on peer_dev->gpu to avoid any potential null pointer > dereferences. > > Addresses-Coverity: ("Dereference on null return value") > Fixes: ae9a25aea7f3 ("drm/amdkfd: Generate xGMI direct iolink") > Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> > --- > drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > index 4e3fc284f6ac..cb6b46cfa6c2 100644 > --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > @@ -1293,7 +1293,7 @@ static int kfd_create_vcrat_image_gpu(void *pcrat_image, > if (kdev->hive_id) { > for (nid = 0; nid < proximity_domain; ++nid) { > peer_dev = kfd_topology_device_by_proximity_domain(nid); > - if (!peer_dev->gpu) > + if (!peer_dev || !peer_dev->gpu) > continue; > if (peer_dev->gpu->hive_id != kdev->hive_id) > continue; _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel