On Tue, 2019-03-12 at 15:44 -0600, Kevin Locke wrote: > On Tue, 2019-03-12 at 20:48 +0000, Grumbach, Emmanuel wrote: > > On Tue, 2019-03-12 at 14:31 -0600, Kevin Locke wrote: > > > On Tue, 2019-03-12 at 19:47 +0000, Grumbach, Emmanuel wrote: > > > > We had issues with reclaim path upon BACK. This is of course a > > > > firmware problem... > > > > > > Does that suggest the issue may have been fixed by a firmware > > > update? > > > For reference, I'm currently using "firmware version 9.221.4.1 > > > build > > > 25532" from the firmware-iwlwifi Debian package (version > > > 20190114-1). > > > > > > If it would be helpful, I could attempt to bisect the firmware > > > revisions to find the one that fixed it (assuming I can reproduce > > > the > > > issue with a previous firmware version). > > > > Well.. Sorry, I wasn't very "technical". > > So the problem was really that we stopped getting BACK > > notifications > > from the firmware and that caused a reclaim stall which in turn was > > caught by a Tx queue stuck timer firing in the driver. > > I was never able to reproduce this. What I can do is to enable A- > > MPDU > > on my old system that has this same device, just to see what > > happens. > > Thanks for the additional details and for offering to try it out, > that > would be great! Just to align on expectations, I don't feel like enable A-MPDU by default regardless of what will come out of this. People stopped complaining after we disabled A-MPDU and the very very very few people that did need more throughput knew how to enable them with the module parameter. So, I don't plan to re-enable A-MPDU by default. > > > While chasing this bug, I even found another one which bought me a > > few > > moments of fame: > > > > commit d6ee27eb13beab94056e0de52d81220058ca2297 > > Author: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx> > > Date: Wed Jun 6 09:13:36 2012 +0200 > > > > iwlwifi: don't mess up the SCD when removing a key > > > > and in the commit message of that very commit: > > > > This doesn't seem to fix the higher queues that get stuck > > from time to time. > > > > There were no new versions of the firmware released since then. > > I tried to skim through bugzilla, but couldn't find the bugs I was > > handling then. > > Ah. You are right about the firmware version. I should have > checked. > > I see what you mean. I found several reports for TX queue stuck > issues in Bugzilla. Perhaps this is one (or one of its many dups): > https://bugzilla.kernel.org/show_bug.cgi?id=56581 > And those were very very time consuming. I don't want to go there again. These are very old devices (they were described as old in 2014 already...). > Let me know if there is anything I can do to help search or test. > > Thanks again, > Kevin
