CC: kbuild-...@lists.01.org BCC: l...@intel.com TO: Maarten Lankhorst <maarten.lankho...@linux.intel.com> CC: Junxiao Chang <junxiao.ch...@intel.com>
tree: https://github.com/intel/linux-intel-lts.git 5.15/linux head: d86220b9804b7e73ffc262a6d8bf5afbbf17be81 commit: 53956aadc1f3755f43e9a8d6741cb2b1d4c58ac6 [336/2399] kernel/locking: Add context to ww_mutex_trylock() :::::: branch date: 5 days ago :::::: commit date: 8 weeks ago config: arm-randconfig-c002-20220417 (https://download.01.org/0day-ci/archive/20220417/202204171609.7n9nq9ac-...@intel.com/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 64c045e25b8471bbb572bd29159c294a82a86a25) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://github.com/intel/linux-intel-lts/commit/53956aadc1f3755f43e9a8d6741cb2b1d4c58ac6 git remote add intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-lts 5.15/linux git checkout 53956aadc1f3755f43e9a8d6741cb2b1d4c58ac6 # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <l...@intel.com> clang-analyzer warnings: (new ones prefixed by >>) ^ include/linux/spinlock_api_up.h:65:35: note: expanded from macro '_raw_spin_lock_irq' #define _raw_spin_lock_irq(lock) __LOCK_IRQ(lock) ^ include/linux/spinlock_api_up.h:37:29: note: expanded from macro '__LOCK_IRQ' do { local_irq_disable(); __LOCK(lock); } while (0) ^ include/linux/spinlock_api_up.h:31:3: note: expanded from macro '__LOCK' do { preempt_disable(); ___LOCK(lock); } while (0) ^ kernel/locking/rtmutex_api.c:394:2: note: Loop condition is false. Exiting loop raw_spin_lock_irq(&lock->wait_lock); ^ include/linux/spinlock.h:286:34: note: expanded from macro 'raw_spin_lock_irq' #define raw_spin_lock_irq(lock) _raw_spin_lock_irq(lock) ^ include/linux/spinlock_api_up.h:65:35: note: expanded from macro '_raw_spin_lock_irq' #define _raw_spin_lock_irq(lock) __LOCK_IRQ(lock) ^ include/linux/spinlock_api_up.h:37:3: note: expanded from macro '__LOCK_IRQ' do { local_irq_disable(); __LOCK(lock); } while (0) ^ kernel/locking/rtmutex_api.c:411:6: note: Assuming the condition is true if (rt_mutex_owner(lock) != current) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex_api.c:411:2: note: Taking true branch if (rt_mutex_owner(lock) != current) { ^ kernel/locking/rtmutex_api.c:412:23: note: Passing value via 2nd parameter 'waiter' remove_waiter(lock, waiter); ^~~~~~ kernel/locking/rtmutex_api.c:412:3: note: Calling 'remove_waiter' remove_waiter(lock, waiter); ^~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:1411:24: note: Assuming pointer value is null bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:1415:2: note: Loop condition is false. Exiting loop lockdep_assert_held(&lock->wait_lock); ^ include/linux/lockdep.h:411:34: note: expanded from macro 'lockdep_assert_held' #define lockdep_assert_held(l) do { (void)(l); } while (0) ^ kernel/locking/rtmutex.c:1417:2: note: Loop condition is false. Exiting loop raw_spin_lock(¤t->pi_lock); ^ include/linux/spinlock.h:229:29: note: expanded from macro 'raw_spin_lock' #define raw_spin_lock(lock) _raw_spin_lock(lock) ^ include/linux/spinlock_api_up.h:58:32: note: expanded from macro '_raw_spin_lock' #define _raw_spin_lock(lock) __LOCK(lock) ^ include/linux/spinlock_api_up.h:31:8: note: expanded from macro '__LOCK' do { preempt_disable(); ___LOCK(lock); } while (0) ^ include/linux/preempt.h:179:27: note: expanded from macro 'preempt_disable' #define preempt_disable() \ ^ kernel/locking/rtmutex.c:1417:2: note: Loop condition is false. Exiting loop raw_spin_lock(¤t->pi_lock); ^ include/linux/spinlock.h:229:29: note: expanded from macro 'raw_spin_lock' #define raw_spin_lock(lock) _raw_spin_lock(lock) ^ include/linux/spinlock_api_up.h:58:32: note: expanded from macro '_raw_spin_lock' #define _raw_spin_lock(lock) __LOCK(lock) ^ include/linux/spinlock_api_up.h:31:27: note: expanded from macro '__LOCK' do { preempt_disable(); ___LOCK(lock); } while (0) ^ include/linux/spinlock_api_up.h:28:3: note: expanded from macro '___LOCK' do { __acquire(lock); (void)(lock); } while (0) ^ kernel/locking/rtmutex.c:1417:2: note: Loop condition is false. Exiting loop raw_spin_lock(¤t->pi_lock); ^ include/linux/spinlock.h:229:29: note: expanded from macro 'raw_spin_lock' #define raw_spin_lock(lock) _raw_spin_lock(lock) ^ include/linux/spinlock_api_up.h:58:32: note: expanded from macro '_raw_spin_lock' #define _raw_spin_lock(lock) __LOCK(lock) ^ include/linux/spinlock_api_up.h:31:3: note: expanded from macro '__LOCK' do { preempt_disable(); ___LOCK(lock); } while (0) ^ kernel/locking/rtmutex.c:1418:25: note: Passing null pointer value via 2nd parameter 'waiter' rt_mutex_dequeue(lock, waiter); ^~~~~~ kernel/locking/rtmutex.c:1418:2: note: Calling 'rt_mutex_dequeue' rt_mutex_dequeue(lock, waiter); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:404:6: note: Access to field '__rb_parent_color' results in a dereference of a null pointer if (RB_EMPTY_NODE(&waiter->tree_entry)) ^ include/linux/rbtree.h:34:3: note: expanded from macro 'RB_EMPTY_NODE' ((node)->__rb_parent_color == (unsigned long)(node)) ^~~~~~~~~~~~~~~~~~~~~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. >> kernel/locking/test-ww_mutex.c:172:2: warning: Undefined or garbage value >> returned to caller [clang-analyzer-core.uninitialized.UndefReturn] return ret; ^ kernel/locking/test-ww_mutex.c:625:2: note: Left side of '&&' is true printk(KERN_INFO "Beginning ww mutex selftests\n"); ^ include/linux/printk.h:450:26: note: expanded from macro 'printk' #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) ^ include/linux/printk.h:421:3: note: expanded from macro 'printk_index_wrap' __printk_index_emit(_fmt, NULL, NULL); \ ^ include/linux/printk.h:374:7: note: expanded from macro '__printk_index_emit' if (__builtin_constant_p(_fmt) && __builtin_constant_p(_level)) { \ ^ kernel/locking/test-ww_mutex.c:625:2: note: Taking true branch printk(KERN_INFO "Beginning ww mutex selftests\n"); ^ include/linux/printk.h:450:26: note: expanded from macro 'printk' #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) ^ include/linux/printk.h:421:3: note: expanded from macro 'printk_index_wrap' __printk_index_emit(_fmt, NULL, NULL); \ ^ include/linux/printk.h:374:3: note: expanded from macro '__printk_index_emit' if (__builtin_constant_p(_fmt) && __builtin_constant_p(_level)) { \ ^ kernel/locking/test-ww_mutex.c:625:2: note: '?' condition is true printk(KERN_INFO "Beginning ww mutex selftests\n"); ^ include/linux/printk.h:450:26: note: expanded from macro 'printk' #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) ^ include/linux/printk.h:421:3: note: expanded from macro 'printk_index_wrap' __printk_index_emit(_fmt, NULL, NULL); \ ^ include/linux/printk.h:383:12: note: expanded from macro '__printk_index_emit' .fmt = __builtin_constant_p(_fmt) ? (_fmt) : NULL, \ ^ kernel/locking/test-ww_mutex.c:625:2: note: '?' condition is true printk(KERN_INFO "Beginning ww mutex selftests\n"); ^ include/linux/printk.h:450:26: note: expanded from macro 'printk' #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) ^ include/linux/printk.h:421:3: note: expanded from macro 'printk_index_wrap' __printk_index_emit(_fmt, NULL, NULL); \ ^ include/linux/printk.h:387:14: note: expanded from macro '__printk_index_emit' .level = __builtin_constant_p(_level) ? (_level) : NULL, \ ^ kernel/locking/test-ww_mutex.c:625:2: note: Loop condition is false. Exiting loop printk(KERN_INFO "Beginning ww mutex selftests\n"); ^ include/linux/printk.h:450:26: note: expanded from macro 'printk' #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) ^ include/linux/printk.h:421:3: note: expanded from macro 'printk_index_wrap' __printk_index_emit(_fmt, NULL, NULL); \ ^ include/linux/printk.h:373:2: note: expanded from macro '__printk_index_emit' do { \ ^ kernel/locking/test-ww_mutex.c:628:6: note: Assuming 'wq' is non-null if (!wq) ^~~ kernel/locking/test-ww_mutex.c:628:2: note: Taking false branch if (!wq) ^ kernel/locking/test-ww_mutex.c:632:6: note: Assuming 'ret' is 0 if (ret) ^~~ kernel/locking/test-ww_mutex.c:632:2: note: Taking false branch if (ret) ^ kernel/locking/test-ww_mutex.c:636:6: note: 'ret' is 0 if (ret) ^~~ kernel/locking/test-ww_mutex.c:636:2: note: Taking false branch if (ret) ^ kernel/locking/test-ww_mutex.c:639:8: note: Calling 'test_aa' ret = test_aa(true); ^~~~~~~~~~~~~ kernel/locking/test-ww_mutex.c:125:2: note: 'ret' declared without an initial value int ret; ^~~~~~~ kernel/locking/test-ww_mutex.c:126:21: note: 'trylock' is true const char *from = trylock ? "trylock" : "lock"; ^~~~~~~ kernel/locking/test-ww_mutex.c:126:21: note: '?' condition is true kernel/locking/test-ww_mutex.c:131:7: note: 'trylock' is true if (!trylock) { ^~~~~~~ kernel/locking/test-ww_mutex.c:131:2: note: Taking false branch if (!trylock) { ^ kernel/locking/test-ww_mutex.c:138:7: note: Assuming the condition is true if (!ww_mutex_trylock(&mutex, &ctx)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/test-ww_mutex.c:138:3: note: Taking true branch vim +172 kernel/locking/test-ww_mutex.c f2a5fec17395f2 Chris Wilson 2016-12-01 120 53956aadc1f375 Maarten Lankhorst 2021-09-09 121 static int test_aa(bool trylock) c22fb3807fd0a3 Chris Wilson 2016-12-01 122 { c22fb3807fd0a3 Chris Wilson 2016-12-01 123 struct ww_mutex mutex; c22fb3807fd0a3 Chris Wilson 2016-12-01 124 struct ww_acquire_ctx ctx; c22fb3807fd0a3 Chris Wilson 2016-12-01 125 int ret; 53956aadc1f375 Maarten Lankhorst 2021-09-09 126 const char *from = trylock ? "trylock" : "lock"; c22fb3807fd0a3 Chris Wilson 2016-12-01 127 c22fb3807fd0a3 Chris Wilson 2016-12-01 128 ww_mutex_init(&mutex, &ww_class); c22fb3807fd0a3 Chris Wilson 2016-12-01 129 ww_acquire_init(&ctx, &ww_class); c22fb3807fd0a3 Chris Wilson 2016-12-01 130 53956aadc1f375 Maarten Lankhorst 2021-09-09 131 if (!trylock) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 132 ret = ww_mutex_lock(&mutex, &ctx); 53956aadc1f375 Maarten Lankhorst 2021-09-09 133 if (ret) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 134 pr_err("%s: initial lock failed!\n", __func__); 53956aadc1f375 Maarten Lankhorst 2021-09-09 135 goto out; 53956aadc1f375 Maarten Lankhorst 2021-09-09 136 } 53956aadc1f375 Maarten Lankhorst 2021-09-09 137 } else { 53956aadc1f375 Maarten Lankhorst 2021-09-09 138 if (!ww_mutex_trylock(&mutex, &ctx)) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 139 pr_err("%s: initial trylock failed!\n", __func__); 53956aadc1f375 Maarten Lankhorst 2021-09-09 140 goto out; 53956aadc1f375 Maarten Lankhorst 2021-09-09 141 } 53956aadc1f375 Maarten Lankhorst 2021-09-09 142 } 53956aadc1f375 Maarten Lankhorst 2021-09-09 143 53956aadc1f375 Maarten Lankhorst 2021-09-09 144 if (ww_mutex_trylock(&mutex, NULL)) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 145 pr_err("%s: trylocked itself without context from %s!\n", __func__, from); 53956aadc1f375 Maarten Lankhorst 2021-09-09 146 ww_mutex_unlock(&mutex); 53956aadc1f375 Maarten Lankhorst 2021-09-09 147 ret = -EINVAL; 53956aadc1f375 Maarten Lankhorst 2021-09-09 148 goto out; 53956aadc1f375 Maarten Lankhorst 2021-09-09 149 } c22fb3807fd0a3 Chris Wilson 2016-12-01 150 53956aadc1f375 Maarten Lankhorst 2021-09-09 151 if (ww_mutex_trylock(&mutex, &ctx)) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 152 pr_err("%s: trylocked itself with context from %s!\n", __func__, from); c22fb3807fd0a3 Chris Wilson 2016-12-01 153 ww_mutex_unlock(&mutex); c22fb3807fd0a3 Chris Wilson 2016-12-01 154 ret = -EINVAL; c22fb3807fd0a3 Chris Wilson 2016-12-01 155 goto out; c22fb3807fd0a3 Chris Wilson 2016-12-01 156 } c22fb3807fd0a3 Chris Wilson 2016-12-01 157 c22fb3807fd0a3 Chris Wilson 2016-12-01 158 ret = ww_mutex_lock(&mutex, &ctx); c22fb3807fd0a3 Chris Wilson 2016-12-01 159 if (ret != -EALREADY) { 53956aadc1f375 Maarten Lankhorst 2021-09-09 160 pr_err("%s: missed deadlock for recursing, ret=%d from %s\n", 53956aadc1f375 Maarten Lankhorst 2021-09-09 161 __func__, ret, from); c22fb3807fd0a3 Chris Wilson 2016-12-01 162 if (!ret) c22fb3807fd0a3 Chris Wilson 2016-12-01 163 ww_mutex_unlock(&mutex); c22fb3807fd0a3 Chris Wilson 2016-12-01 164 ret = -EINVAL; c22fb3807fd0a3 Chris Wilson 2016-12-01 165 goto out; c22fb3807fd0a3 Chris Wilson 2016-12-01 166 } c22fb3807fd0a3 Chris Wilson 2016-12-01 167 53956aadc1f375 Maarten Lankhorst 2021-09-09 168 ww_mutex_unlock(&mutex); c22fb3807fd0a3 Chris Wilson 2016-12-01 169 ret = 0; c22fb3807fd0a3 Chris Wilson 2016-12-01 170 out: c22fb3807fd0a3 Chris Wilson 2016-12-01 171 ww_acquire_fini(&ctx); c22fb3807fd0a3 Chris Wilson 2016-12-01 @172 return ret; c22fb3807fd0a3 Chris Wilson 2016-12-01 173 } c22fb3807fd0a3 Chris Wilson 2016-12-01 174 :::::: The code at line 172 was first introduced by commit :::::: c22fb3807fd0a3bdd98c13c4d2190ab064e6c09d locking/ww_mutex: Add kselftests for ww_mutex AA deadlock detection :::::: TO: Chris Wilson <ch...@chris-wilson.co.uk> :::::: CC: Ingo Molnar <mi...@kernel.org> -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- kbuild@lists.01.org To unsubscribe send an email to kbuild-le...@lists.01.org
