On Monday 29 December 2008 16:56:13 Luis R. Rodriguez wrote: > On Mon, Dec 29, 2008 at 02:28:00AM -0800, Michael Buesch wrote: > > On Monday 29 December 2008 04:45:22 Dan E wrote: > > > > > > On Sun, 28 Dec 2008 00:08:14 +0200, "Jouni Malinen" <j@xxxxx> said: > > > > On Sat, Dec 27, 2008 at 10:08:20PM +0100, Michael Buesch wrote: > > > > > Please take a look at the following log: > > > > > http://bu3sch.de/misc/crda.JPG > > > > > > > > > > Note the ordering of the events. > > > > > Hostapd starts up and tells the kernel what country we're in. > > > > > Then the kernel calls CRDA, _but_ hostapd goes on with its business > > > > > before CRDA has finished its work. > > > > > > > > Yes, because the netlink message was completed and hostapd assumes > > > > everything is ready at that point. Ignoring the complexity in the kernel > > > > (+ CRDA as a helper), this looks like reasonable expectation to make for > > > > NL80211_CMD_REQ_SET_REG operation. There is no other mechanism that > > > > would notify hostapd (or any other program setting country for that > > > > matter) when the operation was actually fully completed and polling for > > > > channel changes up to a timeout is not very appealing either. > > > > > > > > Unfortunately, I don't see an easy fix for this. > > > > > > This sounds like it's broken by design. Hostapd should not send > > > NL80211_CMD_REQ_SET_REG if it is unable to evaluate the result. If it's > > > necessary to do "iw reg set foobar" in a script prior to invoking > > > hostapd, then why does hostapd even bother? > > > > > > > hostapd isn't broken. The CMD_REQ_SET_REG should block until regulatory > > settings are done. It currently doesn't, because that's hard to implement (probably > > by design). > > It means adding a timer and picking a reasonable value for the timeout, > then waiting for a response through nl80211 and disabling the timer from there and > then finally sending the reply back. This seems rather hackish but we can implement > if its desirable. I suppose the worst case scenerio would be CRDA and the > regulatory db in an NFS mount or something like that. I think this wouldn't be hackish, but do we actually _know_ when crda has finished uploading regulatory information? Does it do it all in one step? > An alternative would be for us to add a netlink event once the regultory rule is > set in place. If the first approach is the better path to take then this secondary > netlink event can be sent anyway as informational. Would also be OK, but would also require knowledge about "did we finish already". Do we have this knowledge? -- Greetings, Michael. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
