[BUG] kernel: rcu: a possible sleep-in-atomic-context bug in srcu_read_delay()

[Jia-Ju Bai]

The kernel may sleep with holding a spinlock.

The function call paths (from bottom to top) in Linux-4.16 are:

[FUNC] schedule_timeout_interruptible
kernel/rcu/rcutorture.c, 523: schedule_timeout_interruptible in 
srcu_read_delay
kernel/rcu/rcutorture.c, 1105: [FUNC_PTR]srcu_read_delay in 
rcu_torture_timer
kernel/rcu/rcutorture.c, 1104: spin_lock in rcu_torture_timer

Note that [FUNC_PTR] means a function pointer call is used.

I do not find a good way to fix, so I only report.
This is found by my static analysis tool (DSAC).


Thanks,
Jia-Ju Bai