On 2019-05-29 11:07 a.m., Colin King wrote:

From: Colin Ian King colin.king@canonical.com

The pointer dev is set to null yet it is being dereferenced when checking dev->dqm->sched_policy. Fix this by performing the check on dev->dqm->sched_policy after dev has been assigned and null checked. Also remove the redundant null assignment to dev.

Addresses-Coverity: ("Explicit null dereference") Fixes: 1a058c337676 ("drm/amdkfd: New IOCTL to allocate queue GWS") Signed-off-by: Colin Ian King colin.king@canonical.com

Reviewed-by: Felix Kuehling Felix.Kuehling@amd.com

Thanks!

Felix

---

drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c index aab2aa6c1dee..ea82828fdc76 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c @@ -1572,10 +1572,9 @@ static int kfd_ioctl_alloc_queue_gws(struct file *filep, { int retval; struct kfd_ioctl_alloc_queue_gws_args *args = data;

• struct kfd_dev *dev = NULL;

• struct kfd_dev *dev;

• if (!hws_gws_support ||

• dev->dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS)
  

• if (!hws_gws_support) return -EINVAL;

  dev = kfd_device_by_id(args->gpu_id);

@@ -1583,6 +1582,8 @@ static int kfd_ioctl_alloc_queue_gws(struct file *filep, pr_debug("Could not find gpu id 0x%x\n", args->gpu_id); return -EINVAL; }

• if (dev->dqm->sched_policy == KFD_SCHED_POLICY_NO_HWS)

• return -EINVAL;
  
  

  mutex_lock(&p->mutex); retval = pqm_set_gws(&p->pqm, args->queue_id, args->num_gws ? dev->gws : NULL);