Messages in this thread | | | Date | Wed, 11 Jan 2023 15:48:43 +0100 | From | Frederic Weisbecker <> | Subject | Re: [PATCH] rcu: Fix the start_poll_synchronize_rcu_expedited() be invoked very early |
| |
On Wed, Jan 11, 2023 at 09:14:53PM +0800, Zqiang wrote: > Currently, the start_poll_synchronize_rcu_expedited() can be invoked > very early. before rcu_init(), the rcu_data structure's->mynode is not > initialized, if invoke start_poll_synchronize_rcu_expedited() before > rcu_init(), will access to NULL mynode pointer. > > This commit therefore add exp_seq_poll_rq member to rcu_state structure > to store snap seq number
Is it even sane to poll that early in the morning? :-)
> > Signed-off-by: Zqiang <qiang1.zhang@intel.com> > --- > kernel/rcu/tree.c | 3 ++- > kernel/rcu/tree.h | 1 + > kernel/rcu/tree_exp.h | 6 ++++-- > 3 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index 63545d79da51..34b13d6bd8c4 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -92,6 +92,7 @@ static struct rcu_state rcu_state = { > .exp_mutex = __MUTEX_INITIALIZER(rcu_state.exp_mutex), > .exp_wake_mutex = __MUTEX_INITIALIZER(rcu_state.exp_wake_mutex), > .ofl_lock = __ARCH_SPIN_LOCK_UNLOCKED, > + .exp_seq_poll_rq = RCU_GET_STATE_COMPLETED,
I don't know if we really want to fix this, but assuming we do, can we rename it to boot_exp_seq_poll_rq? To avoid later confusion.
Thanks.
| |