On 29/06/15 09:30, Tom Hughes wrote: > On 29/06/15 09:14, Johannes Berg wrote: >> On Sat, 2015-06-27 at 16:34 +0100, Tom Hughes wrote: >>> >>> Interestingly from what I can see this is trying to create a file >>> for the station at a path something like: >>> >>> ieee80211/phy0/netdev:XXXX/stations/XXXXXX >> >> indeed. >> >>> but in my (currently working) boot under 4.0.4 there is no netdev >>> directory under phy0 in debugfs... but then maybe that is the problem >>> as well if the inode pointer was null? >>> >> >> This is pretty strange - if the dentry pointer (sdata >> ->debugfs.subdir_stations) was NULL or an ERR_PTR(), the code would >> return pretty much immediately. >> >> So it looks like that pointer is valid, but it's ->d_inode was NULL? >> >> I'm not really sure how that could happen. > > Indeed I'm a bit puzzled... It looks like hostapd has something to do with it... If I stop hostapd and remove ath9k and then reprobe it then the netdev dir appears: gosford [~] % sudo modprobe ath9k gosford [~] % sudo ls /sys/kernel/debug/ieee80211/phy1 ath9k long_retry_limit reset user_power fragmentation_threshold netdev:wlp2s0 rts_threshold wep_iv ht40allow_map power short_retry_limit hwflags queues statistics keys rc total_ps_buffered Then I start hostapd and it vanishes: gosford [~] % sudo systemctl start hostapd gosford [~] % sudo ls /sys/kernel/debug/ieee80211/phy1 ath9k keys rc statistics fragmentation_threshold long_retry_limit reset total_ps_buffered ht40allow_map power rts_threshold user_power hwflags queues short_retry_limit wep_iv Tom -- Tom Hughes (tom@xxxxxxxxxx) http://compton.nu/ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html