On Fri, Feb 14, 2020 at 10:55 PM Dennis Dalessandro < dennis.dalessandro@intel.com> wrote: > On 2/14/2020 10:43 AM, Madhuparna Bhowmik wrote: > > > > > > On Wed, Jan 15, 2020 at 12:05 AM > > wrote: > > > > From: Dennis Dalessandro > > > > > > 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@gmail.com > > wrote: > > >>> From: Madhuparna Bhowmik > > > > >>> > > >>> 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 > > >> > > >>> 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. > > > > Hi, > > I just wanted to follow up on this. > > Any updates? > > Also, is the bug fixed now? > > > > Thank you, > > Madhuparna > > > > Thank you, > > Madhuparna > > > > -Denny > > > > I've got a patch going through internal discussion and testing for > adding rcu read locking. > > The RDMAVT patch, I was OK with going in, I guess I just mentioned that > in a reply rather than adding an RB tag. Let me go ahead and do that. > > Thank you very much for the update and Reviewed By. Regards, Madhuparna -Denny >