From: Chris Wilson Date: Fri, 17 Jan 2020 11:06:02 +0000 (+0000) Subject: drm/i915: Satisfy smatch that a loop has at least one iteration X-Git-Tag: v5.7-rc1~136^2~18^2~383 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=416d3838f76b719cb47f076df73691eeac59a6ea;p=users%2Fjedix%2Flinux-maple.git drm/i915: Satisfy smatch that a loop has at least one iteration Smatch worries that the engine->mask may be 0 leading to the loop being shortcircuited leaving the next pointer unset, drivers/gpu/drm/i915/i915_active.c:667 i915_active_acquire_preallocate_barrier() error: uninitialized symbol 'next'. Assert that mask is not 0 and smatch can then verify that next must be initialised before use. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20200117110603.2982286-1-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_active.c b/drivers/gpu/drm/i915/i915_active.c index f3da5c06f331..ace55d5d4ca7 100644 --- a/drivers/gpu/drm/i915/i915_active.c +++ b/drivers/gpu/drm/i915/i915_active.c @@ -621,6 +621,7 @@ int i915_active_acquire_preallocate_barrier(struct i915_active *ref, * We can then use the preallocated nodes in * i915_active_acquire_barrier() */ + GEM_BUG_ON(!mask); for_each_engine_masked(engine, gt, mask, tmp) { u64 idx = engine->kernel_context->timeline->fence_context; struct active_node *node;