include/linux/spinlock_api_smp.h:167:27: sparse: context imbalance in 'wake_futex_pi' - unexpected unlock

From: kbuild test robot
Date: Tue May 09 2017 - 06:56:16 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 2868b2513aa732a99ea4a0a6bf10dc93c1f3dac2
commit: bebe5b514345f09be2c15e414d076b02ecb9cce8 futex: Futex_unlock_pi() determinism
date: 7 weeks ago
reproduce:
# apt-get install sparse
git checkout bebe5b514345f09be2c15e414d076b02ecb9cce8
make ARCH=x86_64 allmodconfig
make C=1 CF=-D__CHECK_ENDIAN__


sparse warnings: (new ones prefixed by >>)

arch/x86/include/asm/futex.h:113:16: sparse: incorrect type in initializer (different address spaces)
arch/x86/include/asm/futex.h:113:16: expected unsigned int [noderef] [usertype] <asn:1>*__uval
arch/x86/include/asm/futex.h:113:16: got unsigned int [usertype] *uval
arch/x86/include/asm/futex.h:113:16: sparse: dereference of noderef expression
>> include/linux/spinlock_api_smp.h:167:27: sparse: context imbalance in 'wake_futex_pi' - unexpected unlock
kernel/futex.c:1577:33: sparse: context imbalance in 'futex_wake_op' - different lock contexts for basic block
kernel/futex.c:1859:41: sparse: context imbalance in 'futex_requeue' - different lock contexts for basic block
include/linux/spinlock_api_smp.h:169:9: sparse: context imbalance in 'fixup_pi_state_owner' - unexpected unlock
kernel/futex.c:2377:13: sparse: context imbalance in 'futex_wait_queue_me' - unexpected unlock
kernel/futex.c:2480:9: sparse: context imbalance in 'futex_wait_setup' - different lock contexts for basic block
kernel/futex.c:2748:12: sparse: context imbalance in 'futex_unlock_pi' - different lock contexts for basic block
kernel/futex.c:3013:29: sparse: context imbalance in 'futex_wait_requeue_pi' - unexpected unlock

vim +/wake_futex_pi +167 include/linux/spinlock_api_smp.h

9828ea9d Thomas Gleixner 2009-12-03 151 do_raw_spin_unlock(lock);
69d0ee73 Heiko Carstens 2009-08-31 152 preempt_enable();
69d0ee73 Heiko Carstens 2009-08-31 153 }
69d0ee73 Heiko Carstens 2009-08-31 154
9c1721aa Thomas Gleixner 2009-12-03 155 static inline void __raw_spin_unlock_irqrestore(raw_spinlock_t *lock,
69d0ee73 Heiko Carstens 2009-08-31 156 unsigned long flags)
69d0ee73 Heiko Carstens 2009-08-31 157 {
69d0ee73 Heiko Carstens 2009-08-31 158 spin_release(&lock->dep_map, 1, _RET_IP_);
9828ea9d Thomas Gleixner 2009-12-03 159 do_raw_spin_unlock(lock);
69d0ee73 Heiko Carstens 2009-08-31 160 local_irq_restore(flags);
69d0ee73 Heiko Carstens 2009-08-31 161 preempt_enable();
69d0ee73 Heiko Carstens 2009-08-31 162 }
69d0ee73 Heiko Carstens 2009-08-31 163
9c1721aa Thomas Gleixner 2009-12-03 164 static inline void __raw_spin_unlock_irq(raw_spinlock_t *lock)
69d0ee73 Heiko Carstens 2009-08-31 165 {
69d0ee73 Heiko Carstens 2009-08-31 166 spin_release(&lock->dep_map, 1, _RET_IP_);
9828ea9d Thomas Gleixner 2009-12-03 @167 do_raw_spin_unlock(lock);
69d0ee73 Heiko Carstens 2009-08-31 168 local_irq_enable();
69d0ee73 Heiko Carstens 2009-08-31 169 preempt_enable();
69d0ee73 Heiko Carstens 2009-08-31 170 }
69d0ee73 Heiko Carstens 2009-08-31 171
9c1721aa Thomas Gleixner 2009-12-03 172 static inline void __raw_spin_unlock_bh(raw_spinlock_t *lock)
69d0ee73 Heiko Carstens 2009-08-31 173 {
69d0ee73 Heiko Carstens 2009-08-31 174 spin_release(&lock->dep_map, 1, _RET_IP_);
9828ea9d Thomas Gleixner 2009-12-03 175 do_raw_spin_unlock(lock);

:::::: The code at line 167 was first introduced by commit
:::::: 9828ea9d75c38fe3dce05d00566eed61c85732e6 locking: Further name space cleanups

:::::: TO: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
:::::: CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

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