[tip:locking/core 5/5] drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:232:34: sparse: sparse: Using plain integer as NULL pointer
From: kernel test robot
Date: Wed Apr 19 2023 - 04:10:56 EST
tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking/core
head: 93eff603d6a2bc1895eeb7063dbd0661bb760b74
commit: f7faedffa92c35afbcfbf0a3dd73079e16b2b87f [5/5] drm/i915/gt: use __xchg instead of internal helper
config: i386-randconfig-s002 (https://download.01.org/0day-ci/archive/20230419/202304191617.HODs4X6a-lkp@xxxxxxxxx/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.4-39-gce1a6720-dirty
# https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=f7faedffa92c35afbcfbf0a3dd73079e16b2b87f
git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
git fetch --no-tags tip locking/core
git checkout f7faedffa92c35afbcfbf0a3dd73079e16b2b87f
# save the config file
mkdir build_dir && cp config build_dir/.config
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 olddefconfig
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/i915/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Link: https://lore.kernel.org/oe-kbuild-all/202304191617.HODs4X6a-lkp@xxxxxxxxx/
sparse warnings: (new ones prefixed by >>)
>> drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:232:34: sparse: sparse: Using plain integer as NULL pointer
drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:247:34: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_engine_cs.c:1045:15: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_lrc.c:1112:37: sparse: sparse: Using plain integer as NULL pointer
drivers/gpu/drm/i915/gt/intel_lrc.c:1229:24: sparse: sparse: Using plain integer as NULL pointer
drivers/gpu/drm/i915/gt/intel_lrc.c:1230:22: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_gt.c:756:21: sparse: sparse: Using plain integer as NULL pointer
drivers/gpu/drm/i915/gt/intel_gt.c:803:14: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_rc6.c:705:16: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_migrate.c:1150:14: sparse: sparse: Using plain integer as NULL pointer
--
>> drivers/gpu/drm/i915/gt/intel_gsc.c:73:43: sparse: sparse: Using plain integer as NULL pointer
vim +232 drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
134
135 static void heartbeat(struct work_struct *wrk)
136 {
137 struct i915_sched_attr attr = { .priority = I915_PRIORITY_MIN };
138 struct intel_engine_cs *engine =
139 container_of(wrk, typeof(*engine), heartbeat.work.work);
140 struct intel_context *ce = engine->kernel_context;
141 struct i915_request *rq;
142 unsigned long serial;
143
144 /* Just in case everything has gone horribly wrong, give it a kick */
145 intel_engine_flush_submission(engine);
146
147 rq = engine->heartbeat.systole;
148 if (rq && i915_request_completed(rq)) {
149 i915_request_put(rq);
150 engine->heartbeat.systole = NULL;
151 }
152
153 if (!intel_engine_pm_get_if_awake(engine))
154 return;
155
156 if (intel_gt_is_wedged(engine->gt))
157 goto out;
158
159 if (i915_sched_engine_disabled(engine->sched_engine)) {
160 reset_engine(engine, engine->heartbeat.systole);
161 goto out;
162 }
163
164 if (engine->heartbeat.systole) {
165 long delay = READ_ONCE(engine->props.heartbeat_interval_ms);
166
167 /* Safeguard against too-fast worker invocations */
168 if (!time_after(jiffies,
169 rq->emitted_jiffies + msecs_to_jiffies(delay)))
170 goto out;
171
172 if (!i915_sw_fence_signaled(&rq->submit)) {
173 /*
174 * Not yet submitted, system is stalled.
175 *
176 * This more often happens for ring submission,
177 * where all contexts are funnelled into a common
178 * ringbuffer. If one context is blocked on an
179 * external fence, not only is it not submitted,
180 * but all other contexts, including the kernel
181 * context are stuck waiting for the signal.
182 */
183 } else if (engine->sched_engine->schedule &&
184 rq->sched.attr.priority < I915_PRIORITY_BARRIER) {
185 /*
186 * Gradually raise the priority of the heartbeat to
187 * give high priority work [which presumably desires
188 * low latency and no jitter] the chance to naturally
189 * complete before being preempted.
190 */
191 attr.priority = 0;
192 if (rq->sched.attr.priority >= attr.priority)
193 attr.priority = I915_PRIORITY_HEARTBEAT;
194 if (rq->sched.attr.priority >= attr.priority)
195 attr.priority = I915_PRIORITY_BARRIER;
196
197 local_bh_disable();
198 engine->sched_engine->schedule(rq, &attr);
199 local_bh_enable();
200 } else {
201 reset_engine(engine, rq);
202 }
203
204 rq->emitted_jiffies = jiffies;
205 goto out;
206 }
207
208 serial = READ_ONCE(engine->serial);
209 if (engine->wakeref_serial == serial)
210 goto out;
211
212 if (!mutex_trylock(&ce->timeline->mutex)) {
213 /* Unable to lock the kernel timeline, is the engine stuck? */
214 if (xchg(&engine->heartbeat.blocked, serial) == serial)
215 intel_gt_handle_error(engine->gt, engine->mask,
216 I915_ERROR_CAPTURE,
217 "no heartbeat on %s",
218 engine->name);
219 goto out;
220 }
221
222 rq = heartbeat_create(ce, GFP_NOWAIT | __GFP_NOWARN);
223 if (IS_ERR(rq))
224 goto unlock;
225
226 heartbeat_commit(rq, &attr);
227
228 unlock:
229 mutex_unlock(&ce->timeline->mutex);
230 out:
231 if (!engine->i915->params.enable_hangcheck || !next_heartbeat(engine))
> 232 i915_request_put(__xchg(&engine->heartbeat.systole, 0));
233 intel_engine_pm_put(engine);
234 }
235
--
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https://github.com/intel/lkp-tests