CC: [email protected] CC: [email protected] CC: [email protected] TO: Thomas Gleixner <[email protected]> CC: Ingo Molnar <[email protected]> CC: "Peter Zijlstra (Intel)" <[email protected]>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 26291c54e111ff6ba87a164d85d4a4e134b7315c commit: 531ae4b06a737ed5539cd75dc6f6b9a28f900bba locking/rtmutex: Split API from implementation date: 6 months ago :::::: branch date: 2 days ago :::::: commit date: 6 months ago config: riscv-randconfig-c006-20220121 (https://download.01.org/0day-ci/archive/20220201/[email protected]/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d4baf3b1322b84816aa623d8e8cb45a49cb68b84) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=531ae4b06a737ed5539cd75dc6f6b9a28f900bba git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 531ae4b06a737ed5539cd75dc6f6b9a28f900bba # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> clang-analyzer warnings: (new ones prefixed by >>) ^ fs/ext4/indirect.c:1254:3: note: Taking false branch if (n == 1) { ^ fs/ext4/indirect.c:1265:17: note: Calling 'ext4_find_shared' partial = p = ext4_find_shared(inode, n, offsets, chain, &nr); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/indirect.c:795:18: note: 'k' is <= 1 for (k = depth; k > 1 && !offsets[k-1]; k--) ^ fs/ext4/indirect.c:795:24: note: Left side of '&&' is false for (k = depth; k > 1 && !offsets[k-1]; k--) ^ fs/ext4/indirect.c:797:12: note: Calling 'ext4_get_branch' partial = ext4_get_branch(inode, k, offsets, chain, &err); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/indirect.c:155:25: note: Left side of '&&' is false add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); ^ include/trace/events/ext4.h:22:24: note: expanded from macro 'EXT4_I' #define EXT4_I(inode) (container_of(inode, struct ext4_inode_info, vfs_inode)) ^ include/linux/kernel.h:495:61: note: expanded from macro 'container_of' BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ ^ fs/ext4/indirect.c:155:25: note: Taking false branch add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); ^ include/trace/events/ext4.h:22:24: note: expanded from macro 'EXT4_I' #define EXT4_I(inode) (container_of(inode, struct ext4_inode_info, vfs_inode)) ^ include/linux/kernel.h:495:2: note: expanded from macro 'container_of' BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ ^ include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^ include/linux/compiler_types.h:328:2: note: expanded from macro 'compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:316:2: note: expanded from macro '_compiletime_assert' __compiletime_assert(condition, msg, prefix, suffix) ^ include/linux/compiler_types.h:308:3: note: expanded from macro '__compiletime_assert' if (!(condition)) \ ^ fs/ext4/indirect.c:155:25: note: Loop condition is false. Exiting loop add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); ^ include/trace/events/ext4.h:22:24: note: expanded from macro 'EXT4_I' #define EXT4_I(inode) (container_of(inode, struct ext4_inode_info, vfs_inode)) ^ include/linux/kernel.h:495:2: note: expanded from macro 'container_of' BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ ^ include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^ include/linux/compiler_types.h:328:2: note: expanded from macro 'compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:316:2: note: expanded from macro '_compiletime_assert' __compiletime_assert(condition, msg, prefix, suffix) ^ include/linux/compiler_types.h:306:2: note: expanded from macro '__compiletime_assert' do { \ ^ fs/ext4/indirect.c:155:47: note: The right operand of '+' is a garbage value add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); ^ ~~~~~~~~ Suppressed 16 warnings (9 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 19 warnings generated. Suppressed 19 warnings (12 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 19 warnings generated. Suppressed 19 warnings (12 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 19 warnings generated. Suppressed 19 warnings (12 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 11 warnings generated. Suppressed 11 warnings (4 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 12 warnings generated. Suppressed 12 warnings (5 in non-user code, 7 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (4 in non-user code, 2 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 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. 11 warnings generated. Suppressed 11 warnings (4 in non-user code, 7 with check filters). 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. 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. 6 warnings generated. >> arch/riscv/include/asm/spinlock.h:24:2: warning: Dereference of null pointer >> [clang-analyzer-core.NullDereference] smp_store_release(&lock->lock, 0); ^ include/asm-generic/barrier.h:138:33: note: expanded from macro 'smp_store_release' #define smp_store_release(p, v) __smp_store_release(p, v) ^ arch/riscv/include/asm/barrier.h:34:2: note: expanded from macro '__smp_store_release' WRITE_ONCE(*p, v); \ ^ include/asm-generic/rwonce.h:61:2: note: expanded from macro 'WRITE_ONCE' __WRITE_ONCE(x, val); \ ^ include/asm-generic/rwonce.h:55:30: note: expanded from macro '__WRITE_ONCE' *(volatile typeof(x) *)&(x) = (val); \ ^ kernel/locking/rtmutex_api.c:419:2: note: Loop condition is false. Exiting loop raw_spin_lock_irqsave(&task->pi_lock, flags); ^ include/linux/spinlock.h:250:2: note: expanded from macro 'raw_spin_lock_irqsave' do { \ ^ kernel/locking/rtmutex_api.c:422:6: note: Assuming 'waiter' is non-null if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) { ^~~~~~~ kernel/locking/rtmutex_api.c:422:6: note: Left side of '||' is false kernel/locking/rtmutex_api.c:422:2: note: Taking false branch if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) { ^ kernel/locking/rtmutex_api.c:427:2: note: Loop condition is false. Exiting loop raw_spin_unlock_irqrestore(&task->pi_lock, flags); ^ include/linux/spinlock.h:288:2: note: expanded from macro 'raw_spin_unlock_irqrestore' do { \ ^ kernel/locking/rtmutex_api.c:432:2: note: Calling 'rt_mutex_adjust_prio_chain' rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:466:6: note: Assuming the condition is false if (++depth > max_lock_depth) { ^~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:466:2: note: Taking false branch if (++depth > max_lock_depth) { ^ kernel/locking/rtmutex.c:510:6: note: Assuming 'waiter' is non-null if (!waiter) ^~~~~~~ kernel/locking/rtmutex.c:510:2: note: Taking false branch if (!waiter) ^ kernel/locking/rtmutex.c:517:6: note: 'orig_waiter' is null if (orig_waiter && !rt_mutex_owner(orig_lock)) ^~~~~~~~~~~ kernel/locking/rtmutex.c:517:18: note: Left side of '&&' is false if (orig_waiter && !rt_mutex_owner(orig_lock)) ^ kernel/locking/rtmutex.c:529:6: note: Assuming 'next_lock' is equal to field 'lock' if (next_lock != waiter->lock) ^~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:529:2: note: Taking false branch if (next_lock != waiter->lock) ^ kernel/locking/rtmutex.c:537:6: note: 'top_waiter' is null if (top_waiter) { ^~~~~~~~~~ kernel/locking/rtmutex.c:537:2: note: Taking false branch if (top_waiter) { ^ kernel/locking/rtmutex.c:561:6: note: Calling 'rt_mutex_waiter_equal' if (rt_mutex_waiter_equal(waiter, task_to_waiter(task))) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:274:6: note: Assuming 'left->prio' is not equal to 'right->prio' if (left->prio != right->prio) ^~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:274:2: note: Taking true branch if (left->prio != right->prio) ^ kernel/locking/rtmutex.c:275:3: note: Returning without writing to 'left->lock' return 0; ^ kernel/locking/rtmutex.c:275:3: note: Returning zero, which participates in a condition later return 0; ^~~~~~~~ kernel/locking/rtmutex.c:561:6: note: Returning from 'rt_mutex_waiter_equal' if (rt_mutex_waiter_equal(waiter, task_to_waiter(task))) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:561:2: note: Taking false branch if (rt_mutex_waiter_equal(waiter, task_to_waiter(task))) { ^ kernel/locking/rtmutex.c:571:2: note: Value assigned to 'lock' lock = waiter->lock; ^~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:577:6: note: Assuming the condition is false if (!raw_spin_trylock(&lock->wait_lock)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:577:2: note: Taking false branch if (!raw_spin_trylock(&lock->wait_lock)) { ^ kernel/locking/rtmutex.c:592:6: note: Assuming 'lock' is equal to 'orig_lock' if (lock == orig_lock || rt_mutex_owner(lock) == top_task) { ^~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:592:24: note: Left side of '||' is true vim +24 arch/riscv/include/asm/spinlock.h fab957c11efe2f Palmer Dabbelt 2017-07-10 21 fab957c11efe2f Palmer Dabbelt 2017-07-10 22 static inline void arch_spin_unlock(arch_spinlock_t *lock) fab957c11efe2f Palmer Dabbelt 2017-07-10 23 { 0123f4d76ca63b Andrea Parri 2018-03-09 @24 smp_store_release(&lock->lock, 0); fab957c11efe2f Palmer Dabbelt 2017-07-10 25 } fab957c11efe2f Palmer Dabbelt 2017-07-10 26 :::::: The code at line 24 was first introduced by commit :::::: 0123f4d76ca63b7b895f40089be0ce4809e392d8 riscv/spinlock: Strengthen implementations with fences :::::: TO: Andrea Parri <[email protected]> :::::: CC: Palmer Dabbelt <[email protected]> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/[email protected] _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
