On Wed, Jan 15, 2020 at 12:04:58AM +0530, madhuparnabhowmik04@xxxxxxxxx wrote: > From: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx> > > On 1/14/2020 12:00 PM, Dennis Dalessandro wrote: > > On 1/14/2020 11:57 AM, Jason Gunthorpe wrote: > > > On Tue, Jan 14, 2020 at 09:53:45PM +0530, > > > madhuparnabhowmik04@xxxxxxxxx wrote: > > > > From: Madhuparna Bhowmik <madhuparnabhowmik04@xxxxxxxxx> > > > > > > > > list_for_each_entry_rcu has built-in RCU and lock checking. > > > > Pass cond argument to list_for_each_entry_rcu. > > > > > > > > Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik04@xxxxxxxxx> > > > > drivers/infiniband/hw/hfi1/verbs.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/infiniband/hw/hfi1/verbs.c > > > > b/drivers/infiniband/hw/hfi1/verbs.c > > > > index 089e201d7550..22f2d4fd2577 100644 > > > > +++ b/drivers/infiniband/hw/hfi1/verbs.c > > > > @@ -515,7 +515,7 @@ static inline void hfi1_handle_packet(struct > > > > hfi1_packet *packet, > > > > opa_get_lid(packet->dlid, 9B)); > > > > if (!mcast) > > > > goto drop; > > > > - list_for_each_entry_rcu(p, &mcast->qp_list, list) { > > > > + list_for_each_entry_rcu(p, &mcast->qp_list, list, > > > > lockdep_is_held(&(ibp->rvp.lock))) { > > > > > > Okay, this looks reasonable > > > > > > Mike, Dennis, is this the right lock to test? > > > > > > > I'm looking at that right now actually, I don't think this is correct. > > Wanted to talk to Mike before I send a response though. > > > > -Denny > > That's definitely going to throw a ton of lock dep messages. It's not really > the right lock either. Instead what we probably need to do is what we do in > the non-multicast part of the code and take the rcu_read_lock(). > > I'd say hold off on this and we'll fix it right. Same goes for the qib one. > > Alright, thank you for reviewing. > > The rdmavt one though looks to be OK. I'll give it a test. Madhuparna, there seems to be an issue with your mail client where it is not quoting text correctly, either there is a '>' missing or there are too many. Can you look into it and figure what's wrong with it? thanks, - Joel > > Thank you, > Madhuparna > > -Denny