On Sun, 2022-02-27 at 17:21 -0800, Robert Joslyn wrote: > I have laptop with an Intel AX200 Wi-Fi controller and everything works > fine in a 5.14 kernel, but in 5.15 or later, the adapter does not work > most of the time. In maybe 9 out of 10 boots in 5.15+, the wlan0 > interface does not get created. The hardware is detected and shows up > in lspci, the iwlwifi driver is loaded, but no interface is created. Do you see any deadlocks? Stuck tasks? Is the machine usable at this point? Can you run "ip link" commands etc.? It seems weird that such an obvious locking problem would have an "only" 90% failure rate... > If I remove the call to rtnl_lock and rtnl_unlock added in those > commits from 5.17.0-rc4, everything works again (but dmesg has a bunch > of RTNL assertion failures from the missing lock). I assume there is a > race or deadlock somewhere, but I've not been able to find it. I'm not > at all familiar with this part of the kernel so perhaps that's not > surprising :-) > > Any thoughts as to what might be going wrong or suggestions on further > debugging? > See above - and maybe you can have lockdep in the kernel? johannes
