> > On 12/17/2013 11:06 PM, Linus Torvalds wrote: > > We have literally had this *exact* same issue with firmware loading. > > Network drivers shouldn't try to load firmware at module load time. > > Same deal. > > It is kind of a chicken and egg problem for (wireless) networking drivers. To > get IFF_UP from the network layer you have to register a netdevice. For > wireless drivers this means you have to register a wiphy device with cfg80211 > which flags capabilities and optionally are custom regulatory domain. That > information depends on the device and firmware used. And there we have a > full circle. >
To solve this - iwlwifi uses request_firmware_nowait. Its doc reads: "Asynchronous variant of request_firmware for user contexts: - sleep for as small periods as possible since it may increase kernel boot time of built-in device drivers requesting firmware in their ->probe methods, if gfp is GFP_KERNEL."
