From: kernel test robot <lkp(a)intel.com&gt; drivers/gpu/drm/i915/gt/gen6_ppgtt.c:263:6-8: ERROR: iterator variable bound on line 262 cannot be NULL drivers/gpu/drm/i915/gt/gen6_ppgtt.c:322:7-9: ERROR: iterator variable bound on line 321 cannot be NULL Many iterators have the property that the first argument is always bound to a real list element, never NULL. Semantic patch information: False positives arise for some iterators that do not have this property, or in cases when the loop cursor is reassigned. The latter should only happen when the matched code is on the way to a loop exit (break, goto, or return). Generated by: scripts/coccinelle/iterators/itnull.cocci Fixes: 1d567ec61933 ("drm/i915/gt: Switch to object allocations for page directories") Signed-off-by: kernel test robot <lkp(a)intel.com&gt; --- tree: git://anongit.freedesktop.org/drm-intel drm-intel-next-queued head: 06b108297b5cc24418e91c1103587ac7ca6fd03f commit: 1d567ec619333e54283dcd02780ab9a71ef86e44 [27/28] drm/i915/gt: Switch to object allocations for page directories Please take the patch only if it's a positive warning. Thanks! gen6_ppgtt.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c +++ b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c @@ -260,8 +260,9 @@ static void gen6_ppgtt_free_pd(struct ge u32 pde; gen6_for_all_pdes(pt, pd, pde) - if (pt) - free_px(&ppgtt->base.vm, pt); + { + free_px(&ppgtt->base.vm, pt); + } } static void gen6_ppgtt_cleanup(struct i915_address_space *vm) @@ -319,7 +320,7 @@ static void pd_vma_unbind(struct i915_ad /* Free all no longer used page tables */ gen6_for_all_pdes(pt, ppgtt->base.pd, pde) { - if (!pt || atomic_read(&pt->used)) + if (atomic_read(&pt->used)) continue; free_px(&ppgtt->base.vm, pt);