On Thu, 3 Aug 2017, Coelho, Luciano wrote: > Okay, so as I understand it the problem has been there for a long time, > but the splat is only coming up now because of Thomas' patch that adds > the lockdep map[1], right? Yeah, sorry, forgot to mention that pre-49dfe2a67797 kernels wouldn't produce this, as there would not be aware of the fact that cpus_read_lock() is actually semantically a lock. > I see the workqueue allocation you mentioned. I'll try to move this > allocation out of the mutex and see how it goes. I have been briefly looking into this as well -- it'll basically have to be moved out of the trans_pcie->mutex context, but (a) I'm not sure whether that's actually safe (b) iwl_pcie_rx_reuse_rbd() (which is where corresponding work is being queued) is not a proper context either (it's atomic context) Thanks, -- Jiri Kosina SUSE Labs