Linux Driver Verification » Linux Kernel Safety RuleDB

Feature #3242

Updated by Denis Efremov over 12 years ago

From documentation: 
 lockdep will complain if you access rcu_dereference() outside of an RCU read-side critical section.    See lockdep.txt to learn what to do about this. 

 In addition, a separate kernel config parameter CONFIG_PROVE_RCU enables 
 checking of rcu_dereference() primitives: 

         rcu_dereference(p): 
                 Check for RCU read-side critical section. 
         rcu_dereference_bh(p): 
                 Check for RCU-bh read-side critical section. 
         rcu_dereference_sched(p): 
                 Check for RCU-sched read-side critical section. 
         srcu_dereference(p, sp): 
                 Check for SRCU read-side critical section. 



 


 I think that we should also check rcu_read_lock/rcu_read_unlock pair for the absence of rcu_dereference. Such behaviour is allowed on x86 but will lead to the errors on Alpha architecture. It is an example of improper use of rcu_lock technique.

Back