From: kernel test robot <lkp@intel.com>
To: elver@google.com
Cc: oe-kbuild-all@lists.linux.dev
Subject: [melver:cap-analysis/dev 30/31] include/linux/sched/task.h:231:1: warning: spinlock 'p->.alloc_lock' is still held at the end of function
Date: Thu, 20 Feb 2025 03:21:15 +0800 [thread overview]
Message-ID: <202502200305.Fr12eLSo-lkp@intel.com> (raw)
tree: https://git.kernel.org/pub/scm/linux/kernel/git/melver/linux.git cap-analysis/dev
head: e064f46a74e53c4986a0acc07a4c60dbea0b0aa5
commit: 26bf30e9185ae72092b427b8a21621b0838354e4 [30/31] drivers/tty: Enable capability analysis for core files
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20250220/202502200305.Fr12eLSo-lkp@intel.com/config)
compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project 910be4ff90d7d07bd4518ea03b85c0974672bf9c)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250220/202502200305.Fr12eLSo-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202502200305.Fr12eLSo-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from drivers/tty/tty_io.c:73:
In file included from include/linux/sched/signal.h:9:
>> include/linux/sched/task.h:231:1: warning: spinlock 'p->.alloc_lock' is still held at the end of function [-Wthread-safety-analysis]
231 | }
| ^
include/linux/sched/task.h:230:2: note: spinlock acquired here
230 | spin_lock(&p->alloc_lock);
| ^
>> include/linux/sched/task.h:235:2: warning: releasing spinlock 'p->.alloc_lock' that was not held [-Wthread-safety-analysis]
235 | spin_unlock(&p->alloc_lock);
| ^
In file included from drivers/tty/tty_io.c:73:
>> include/linux/sched/signal.h:741:2: warning: releasing spinlock 'task->.sighand->siglock' that was not held [-Wthread-safety-analysis]
741 | spin_unlock_irqrestore(&task->sighand->siglock, *flags);
| ^
In file included from drivers/tty/tty_io.c:75:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:131:
In file included from include/asm-generic/io.h:1108:
include/linux/pgtable.h:136:2: warning: releasing __capability_RCU 'RCU' that was not held [-Wthread-safety-analysis]
136 | rcu_read_unlock();
| ^
In file included from drivers/tty/tty_io.c:75:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:578:
In file included from include/linux/irqdesc.h:6:
In file included from include/linux/kobject.h:20:
In file included from include/linux/sysfs.h:16:
In file included from include/linux/kernfs.h:12:
In file included from include/linux/idr.h:15:
include/linux/radix-tree.h:260:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
260 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
| ^
include/linux/compiler-capability-analysis.h:291:23: note: expanded from macro '__release'
291 | #define __release(x) __release_cap(x)
| ^
In file included from drivers/tty/tty_io.c:75:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:578:
In file included from include/linux/irqdesc.h:6:
In file included from include/linux/kobject.h:20:
In file included from include/linux/sysfs.h:16:
In file included from include/linux/kernfs.h:12:
include/linux/idr.h:174:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
174 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
| ^
include/linux/compiler-capability-analysis.h:291:23: note: expanded from macro '__release'
291 | #define __release(x) __release_cap(x)
| ^
In file included from drivers/tty/tty_io.c:75:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
include/linux/irq.h:1226:1: warning: raw_spinlock 'gc->lock' is still held at the end of function [-Wthread-safety-analysis]
1226 | }
| ^
include/linux/irq.h:1225:2: note: raw_spinlock acquired here
1225 | raw_spin_lock(&gc->lock);
| ^
include/linux/spinlock.h:218:29: note: expanded from macro 'raw_spin_lock'
218 | #define raw_spin_lock(lock) _raw_spin_lock(lock)
| ^
In file included from drivers/tty/tty_io.c:75:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
include/linux/irq.h:1230:2: warning: releasing raw_spinlock 'gc->lock' that was not held [-Wthread-safety-analysis]
1230 | raw_spin_unlock(&gc->lock);
| ^
include/linux/spinlock.h:277:32: note: expanded from macro 'raw_spin_unlock'
277 | #define raw_spin_unlock(lock) _raw_spin_unlock(lock)
| ^
In file included from drivers/tty/tty_io.c:75:
include/linux/interrupt.h:239:1: warning: 'assert_capability' attribute requires arguments whose type is annotated with 'capability' attribute; type here is 'int *' [-Wthread-safety-attributes]
239 | DEFINE_LOCK_GUARD_1(disable_irq, int,
| ^
include/linux/cleanup.h:413:60: note: expanded from macro 'DEFINE_LOCK_GUARD_1'
413 | __DEFINE_UNLOCK_GUARD(_name, _type, _unlock, __VA_ARGS__) \
| ^
include/linux/cleanup.h:390:27: note: expanded from macro '\
__DEFINE_LOCK_GUARD_1'
390 | __no_capability_analysis __asserts_cap(l) \
| ^
include/linux/compiler-capability-analysis.h:21:46: note: expanded from macro '__asserts_cap'
21 | # define __asserts_cap(var) __attribute__((assert_capability(var)))
| ^
In file included from drivers/tty/tty_io.c:76:
In file included from include/linux/tty.h:5:
--
In file included from drivers/tty/n_tty.c:40:
In file included from include/linux/poll.h:10:
In file included from include/linux/fs.h:15:
include/linux/radix-tree.h:260:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
260 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
| ^
include/linux/compiler-capability-analysis.h:291:23: note: expanded from macro '__release'
291 | #define __release(x) __release_cap(x)
| ^
In file included from drivers/tty/n_tty.c:40:
In file included from include/linux/poll.h:10:
In file included from include/linux/fs.h:33:
In file included from include/linux/percpu-rwsem.h:7:
In file included from include/linux/rcuwait.h:6:
In file included from include/linux/sched/signal.h:9:
>> include/linux/sched/task.h:231:1: warning: spinlock 'p->.alloc_lock' is still held at the end of function [-Wthread-safety-analysis]
231 | }
| ^
include/linux/sched/task.h:230:2: note: spinlock acquired here
230 | spin_lock(&p->alloc_lock);
| ^
>> include/linux/sched/task.h:235:2: warning: releasing spinlock 'p->.alloc_lock' that was not held [-Wthread-safety-analysis]
235 | spin_unlock(&p->alloc_lock);
| ^
In file included from drivers/tty/n_tty.c:40:
In file included from include/linux/poll.h:10:
In file included from include/linux/fs.h:33:
In file included from include/linux/percpu-rwsem.h:7:
In file included from include/linux/rcuwait.h:6:
>> include/linux/sched/signal.h:741:2: warning: releasing spinlock 'task->.sighand->siglock' that was not held [-Wthread-safety-analysis]
741 | spin_unlock_irqrestore(&task->sighand->siglock, *flags);
| ^
In file included from drivers/tty/n_tty.c:40:
In file included from include/linux/poll.h:10:
include/linux/fs.h:545:1: warning: rw_semaphore 'mapping->i_mmap_rwsem' is still held at the end of function [-Wthread-safety-analysis]
545 | }
| ^
include/linux/fs.h:544:2: note: rw_semaphore acquired here
544 | down_write(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:554:2: warning: releasing rw_semaphore 'mapping->i_mmap_rwsem' that was not held [-Wthread-safety-analysis]
554 | up_write(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:565:1: warning: rw_semaphore 'mapping->i_mmap_rwsem' is still held at the end of function [-Wthread-safety-analysis]
565 | }
| ^
include/linux/fs.h:564:2: note: rw_semaphore acquired here
564 | down_read(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:569:2: warning: releasing rw_semaphore 'mapping->i_mmap_rwsem' that was not held [-Wthread-safety-analysis]
569 | up_read(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:878:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
878 | }
| ^
include/linux/fs.h:877:2: note: rw_semaphore acquired here
877 | down_write(&inode->i_rwsem);
| ^
include/linux/fs.h:882:2: warning: releasing rw_semaphore 'inode->i_rwsem' that was not held [-Wthread-safety-analysis]
882 | up_write(&inode->i_rwsem);
| ^
include/linux/fs.h:888:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
888 | }
| ^
include/linux/fs.h:887:2: note: rw_semaphore acquired here
887 | down_read(&inode->i_rwsem);
| ^
include/linux/fs.h:892:2: warning: releasing rw_semaphore 'inode->i_rwsem' that was not held [-Wthread-safety-analysis]
892 | up_read(&inode->i_rwsem);
| ^
include/linux/fs.h:913:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
913 | }
| ^
include/linux/fs.h:912:2: note: rw_semaphore acquired here
912 | down_write_nested(&inode->i_rwsem, subclass);
| ^
include/linux/fs.h:918:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
918 | }
| ^
include/linux/fs.h:917:2: note: rw_semaphore acquired here
917 | down_read_nested(&inode->i_rwsem, subclass);
| ^
include/linux/fs.h:923:1: warning: rw_semaphore 'mapping->invalidate_lock' is still held at the end of function [-Wthread-safety-analysis]
923 | }
| ^
include/linux/fs.h:922:2: note: rw_semaphore acquired here
922 | down_write(&mapping->invalidate_lock);
| ^
include/linux/fs.h:927:2: warning: releasing rw_semaphore 'mapping->invalidate_lock' that was not held [-Wthread-safety-analysis]
927 | up_write(&mapping->invalidate_lock);
| ^
include/linux/fs.h:933:1: warning: rw_semaphore 'mapping->invalidate_lock' is still held at the end of function [-Wthread-safety-analysis]
933 | }
| ^
include/linux/fs.h:932:2: note: rw_semaphore acquired here
932 | down_read(&mapping->invalidate_lock);
| ^
include/linux/fs.h:944:2: warning: releasing rw_semaphore 'mapping->invalidate_lock' that was not held [-Wthread-safety-analysis]
944 | up_read(&mapping->invalidate_lock);
| ^
In file included from drivers/tty/n_tty.c:46:
In file included from include/linux/tty.h:9:
In file included from include/linux/tty_driver.h:9:
In file included from include/linux/cdev.h:5:
In file included from include/linux/kobject.h:20:
In file included from include/linux/sysfs.h:16:
In file included from include/linux/kernfs.h:12:
include/linux/idr.h:174:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
174 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
| ^
include/linux/compiler-capability-analysis.h:291:23: note: expanded from macro '__release'
291 | #define __release(x) __release_cap(x)
| ^
In file included from drivers/tty/n_tty.c:46:
In file included from include/linux/tty.h:9:
In file included from include/linux/tty_driver.h:9:
In file included from include/linux/cdev.h:8:
include/linux/device.h:1031:1: warning: mutex 'dev->mutex' is still held at the end of function [-Wthread-safety-analysis]
1031 | }
| ^
include/linux/device.h:1030:2: note: mutex acquired here
1030 | mutex_lock(&dev->mutex);
| ^
include/linux/mutex.h:167:26: note: expanded from macro 'mutex_lock'
--
In file included from drivers/tty/tty_ioctl.c:14:
In file included from include/linux/sched/signal.h:9:
>> include/linux/sched/task.h:231:1: warning: spinlock 'p->.alloc_lock' is still held at the end of function [-Wthread-safety-analysis]
231 | }
| ^
include/linux/sched/task.h:230:2: note: spinlock acquired here
230 | spin_lock(&p->alloc_lock);
| ^
>> include/linux/sched/task.h:235:2: warning: releasing spinlock 'p->.alloc_lock' that was not held [-Wthread-safety-analysis]
235 | spin_unlock(&p->alloc_lock);
| ^
In file included from drivers/tty/tty_ioctl.c:14:
>> include/linux/sched/signal.h:741:2: warning: releasing spinlock 'task->.sighand->siglock' that was not held [-Wthread-safety-analysis]
741 | spin_unlock_irqrestore(&task->sighand->siglock, *flags);
| ^
In file included from drivers/tty/tty_ioctl.c:17:
In file included from include/linux/tty.h:5:
In file included from include/linux/fs.h:15:
include/linux/radix-tree.h:260:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
260 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
| ^
include/linux/compiler-capability-analysis.h:291:23: note: expanded from macro '__release'
291 | #define __release(x) __release_cap(x)
| ^
In file included from drivers/tty/tty_ioctl.c:17:
In file included from include/linux/tty.h:5:
include/linux/fs.h:545:1: warning: rw_semaphore 'mapping->i_mmap_rwsem' is still held at the end of function [-Wthread-safety-analysis]
545 | }
| ^
include/linux/fs.h:544:2: note: rw_semaphore acquired here
544 | down_write(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:554:2: warning: releasing rw_semaphore 'mapping->i_mmap_rwsem' that was not held [-Wthread-safety-analysis]
554 | up_write(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:565:1: warning: rw_semaphore 'mapping->i_mmap_rwsem' is still held at the end of function [-Wthread-safety-analysis]
565 | }
| ^
include/linux/fs.h:564:2: note: rw_semaphore acquired here
564 | down_read(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:569:2: warning: releasing rw_semaphore 'mapping->i_mmap_rwsem' that was not held [-Wthread-safety-analysis]
569 | up_read(&mapping->i_mmap_rwsem);
| ^
include/linux/fs.h:878:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
878 | }
| ^
include/linux/fs.h:877:2: note: rw_semaphore acquired here
877 | down_write(&inode->i_rwsem);
| ^
include/linux/fs.h:882:2: warning: releasing rw_semaphore 'inode->i_rwsem' that was not held [-Wthread-safety-analysis]
882 | up_write(&inode->i_rwsem);
| ^
include/linux/fs.h:888:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
888 | }
| ^
include/linux/fs.h:887:2: note: rw_semaphore acquired here
887 | down_read(&inode->i_rwsem);
| ^
include/linux/fs.h:892:2: warning: releasing rw_semaphore 'inode->i_rwsem' that was not held [-Wthread-safety-analysis]
892 | up_read(&inode->i_rwsem);
| ^
include/linux/fs.h:913:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
913 | }
| ^
include/linux/fs.h:912:2: note: rw_semaphore acquired here
912 | down_write_nested(&inode->i_rwsem, subclass);
| ^
include/linux/fs.h:918:1: warning: rw_semaphore 'inode->i_rwsem' is still held at the end of function [-Wthread-safety-analysis]
918 | }
| ^
include/linux/fs.h:917:2: note: rw_semaphore acquired here
917 | down_read_nested(&inode->i_rwsem, subclass);
| ^
include/linux/fs.h:923:1: warning: rw_semaphore 'mapping->invalidate_lock' is still held at the end of function [-Wthread-safety-analysis]
923 | }
| ^
include/linux/fs.h:922:2: note: rw_semaphore acquired here
922 | down_write(&mapping->invalidate_lock);
| ^
include/linux/fs.h:927:2: warning: releasing rw_semaphore 'mapping->invalidate_lock' that was not held [-Wthread-safety-analysis]
927 | up_write(&mapping->invalidate_lock);
| ^
include/linux/fs.h:933:1: warning: rw_semaphore 'mapping->invalidate_lock' is still held at the end of function [-Wthread-safety-analysis]
933 | }
| ^
include/linux/fs.h:932:2: note: rw_semaphore acquired here
932 | down_read(&mapping->invalidate_lock);
| ^
include/linux/fs.h:944:2: warning: releasing rw_semaphore 'mapping->invalidate_lock' that was not held [-Wthread-safety-analysis]
944 | up_read(&mapping->invalidate_lock);
| ^
In file included from drivers/tty/tty_ioctl.c:17:
In file included from include/linux/tty.h:9:
In file included from include/linux/tty_driver.h:9:
In file included from include/linux/cdev.h:5:
In file included from include/linux/kobject.h:20:
In file included from include/linux/sysfs.h:16:
In file included from include/linux/kernfs.h:12:
include/linux/idr.h:174:2: warning: releasing local_lock 'radix_tree_preloads.lock' that was not held [-Wthread-safety-analysis]
174 | local_unlock(&radix_tree_preloads.lock);
| ^
include/linux/local_lock.h:37:29: note: expanded from macro 'local_unlock'
37 | #define local_unlock(lock) __local_unlock(lock)
| ^
include/linux/local_lock_internal.h:103:3: note: expanded from macro '__local_unlock'
103 | __release(lock); \
..
vim +231 include/linux/sched/task.h
901b14bd946a8b Ingo Molnar 2017-02-03 217
56cd697366b6d6 Ingo Molnar 2017-02-06 218 /*
56cd697366b6d6 Ingo Molnar 2017-02-06 219 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
56cd697366b6d6 Ingo Molnar 2017-02-06 220 * subscriptions and synchronises with wait4(). Also used in procfs. Also
56cd697366b6d6 Ingo Molnar 2017-02-06 221 * pins the final release of task.io_context. Also protects ->cpuset and
85b6d24646e412 Alexander Mikhalitsyn 2021-11-19 222 * ->cgroup.subsys[]. And ->vfork_done. And ->sysvshm.shm_clist.
56cd697366b6d6 Ingo Molnar 2017-02-06 223 *
56cd697366b6d6 Ingo Molnar 2017-02-06 224 * Nests both inside and outside of read_lock(&tasklist_lock).
56cd697366b6d6 Ingo Molnar 2017-02-06 225 * It must not be nested with write_lock_irq(&tasklist_lock),
56cd697366b6d6 Ingo Molnar 2017-02-06 226 * neither inside nor outside.
56cd697366b6d6 Ingo Molnar 2017-02-06 227 */
56cd697366b6d6 Ingo Molnar 2017-02-06 228 static inline void task_lock(struct task_struct *p)
56cd697366b6d6 Ingo Molnar 2017-02-06 229 {
56cd697366b6d6 Ingo Molnar 2017-02-06 230 spin_lock(&p->alloc_lock);
56cd697366b6d6 Ingo Molnar 2017-02-06 @231 }
56cd697366b6d6 Ingo Molnar 2017-02-06 232
56cd697366b6d6 Ingo Molnar 2017-02-06 233 static inline void task_unlock(struct task_struct *p)
56cd697366b6d6 Ingo Molnar 2017-02-06 234 {
56cd697366b6d6 Ingo Molnar 2017-02-06 @235 spin_unlock(&p->alloc_lock);
56cd697366b6d6 Ingo Molnar 2017-02-06 236 }
56cd697366b6d6 Ingo Molnar 2017-02-06 237
:::::: The code at line 231 was first introduced by commit
:::::: 56cd697366b6d6f67acb6c58ac7f3b185d11ef07 sched/headers: Move the task_lock()/unlock() APIs to <linux/sched/task.h>
:::::: TO: Ingo Molnar <mingo@kernel.org>
:::::: CC: Ingo Molnar <mingo@kernel.org>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
reply other threads:[~2025-02-19 19:26 UTC|newest]
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