When starting CAC in a mode other than AP mode, it return a "WARNING: CPU: 0 PID: 63 at cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211]" caused by the chandef.chan being null at the end of CAC. Solution: Ensure the channel definition is set for the different modes when starting CAC to avoid getting a NULL 'chan' at the end of CAC. Call Trace: ? show_regs.part.0+0x14/0x16 ? __warn+0x67/0xc0 ? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211] ? report_bug+0xa7/0x130 ? exc_overflow+0x30/0x30 ? handle_bug+0x27/0x50 ? exc_invalid_op+0x18/0x60 ? handle_exception+0xf6/0xf6 ? exc_overflow+0x30/0x30 ? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211] ? exc_overflow+0x30/0x30 ? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211] ? regulatory_propagate_dfs_state.cold+0x1b/0x4c [cfg80211] ? cfg80211_propagate_cac_done_wk+0x1a/0x30 [cfg80211] ? process_one_work+0x165/0x280 ? worker_thread+0x120/0x3f0 ? kthread+0xc2/0xf0 ? process_one_work+0x280/0x280 ? kthread_complete_and_exit+0x20/0x20 ? ret_from_fork+0x19/0x24 Signed-off-by: Issam Hamdi <ih@xxxxxxxxxxxxxxxxxx> Signed-off-by: Kretschmer Mathias <mathias.kretschmer@xxxxxxxxxxxxxxxxx> --- --- v2: update the subject v3: update the second Signed-off-by to Reported-by v4: Remove the check on the OCB mode --- net/wireless/nl80211.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 7397a372c78e..60cf6d3dd3ca 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -10143,7 +10143,20 @@ static int nl80211_start_radar_detection(struct sk_buff *skb, err = rdev_start_radar_detection(rdev, dev, &chandef, cac_time_ms); if (!err) { - wdev->links[0].ap.chandef = chandef; + switch (wdev->iftype) { + case NL80211_IFTYPE_MESH_POINT: + wdev->u.mesh.chandef = chandef; + break; + case NL80211_IFTYPE_ADHOC: + wdev->u.ibss.chandef = chandef; + break; + case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_P2P_GO: + wdev->links[0].ap.chandef = chandef; + break; + default: + break; + } wdev->cac_started = true; wdev->cac_start_time = jiffies; wdev->cac_time_ms = cac_time_ms; base-commit: cc32e9fb380d8afdbf3486d7063d5520bfb0f071 -- 2.39.2