[kbuild-all] [kbuild] drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:2376 eb_pin_timeline() warn: inconsistent returns '&tl->mutex'.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: dfd42facf1e4ada021b939b4e19c935dcdd55566 commit: 544460c33821b44c2f0c643121303c3dc3f66ef1 drm/i915: Multi-BB execbuf config: i386-randconfig-m021-20220207 (https://download.01.org/0day-ci/archive/20220207/202202072340.xZpz7hAb-lk... ) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; New smatch warnings: drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:2376 eb_pin_timeline() warn: inconsistent returns '&tl->mutex'. vim +2376 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2333 static int eb_pin_timeline(struct i915_execbuffer *eb, struct intel_context *ce, 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2334 bool throttle) 8f2a1057d6ec21 drivers/gpu/drm/i915/i915_gem_execbuffer.c Chris Wilson 2019-04-25 2335 { e5dadff4b09376 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-15 2336 struct intel_timeline *tl; 2bf541ff6d06f4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Maarten Lankhorst 2020-08-19 2337 struct i915_request *rq = NULL; 8f2a1057d6ec21 drivers/gpu/drm/i915/i915_gem_execbuffer.c Chris Wilson 2019-04-25 2338 a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2339 /* a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2340 * Take a local wakeref for preparing to dispatch the execbuf as a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2341 * we expect to access the hardware fairly frequently in the a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2342 * process, and require the engine to be kept awake between accesses. a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2343 * Upon dispatch, we acquire another prolonged wakeref that we hold a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2344 * until the timeline is idle, which in turn releases the wakeref a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2345 * taken on the engine, and the parent device. a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2346 */ e5dadff4b09376 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-15 2347 tl = intel_context_timeline_lock(ce); 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2348 if (IS_ERR(tl)) 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2349 return PTR_ERR(tl); a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2350 a4e57f9031ccd5 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-04 2351 intel_context_enter(ce); 2bf541ff6d06f4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Maarten Lankhorst 2020-08-19 2352 if (throttle) 2bf541ff6d06f4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Maarten Lankhorst 2020-08-19 2353 rq = eb_throttle(eb, ce); e5dadff4b09376 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-15 2354 intel_context_timeline_unlock(tl); e5dadff4b09376 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Chris Wilson 2019-08-15 2355 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2356 if (rq) { 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2357 bool nonblock = eb->file->filp->f_flags & O_NONBLOCK; 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2358 long timeout = nonblock ? 0 : MAX_SCHEDULE_TIMEOUT; 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2359 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2360 if (i915_request_wait(rq, I915_WAIT_INTERRUPTIBLE, 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2361 timeout) < 0) { 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2362 i915_request_put(rq); 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2363 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2364 tl = intel_context_timeline_lock(ce); This is mutex_lock_interruptible() so it can fail 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2365 intel_context_exit(ce); 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2366 intel_context_timeline_unlock(tl); Leading to an error pointer dereference. Maybe that's why Smatch is complaining? Hard to say. Why are we calling mutex_lock if it's O_NONBLOCK code? 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2367 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2368 if (nonblock) 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2369 return -EWOULDBLOCK; 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2370 else 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2371 return -EINTR; 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2372 } 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2373 i915_request_put(rq); 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2374 } 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2375 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 @2376 return 0; 544460c33821b4 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c Matthew Brost 2021-10-14 2377 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org _______________________________________________ kbuild mailing list -- kbuild(a)lists.01.org To unsubscribe send an email to kbuild-leave(a)lists.01.org