EXP smp/hotplug,lockdep: Annotate cpuhp_state
After the st->done annotation, lockdep cross-release now complains
about:
CPU0 CPU1 CPU2
cpuhp_up_callbacks: takedown_cpu: cpuhp_thread_fun:
cpuhp_state
irq_lock_sparse()
irq_lock_sparse()
wait_for_completion()
cpuhp_state
complete()
which again spells deadlock, because CPU0 needs to wait for CPU1's
irq_lock_sparse which will wait for CPU2's completion, which in turn
waits for CPU0's cpuhp_state.
Now, this again mixes up and down chains, but now on cpuhp_state.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Byungchul Park <max.byungchul.park@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reported-by: Mike Galbraith <efault@gmx.de>
Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
1 file changed
