From e7441c9274a6a5453e06f4c2b8b5f72eca0a3f17 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Tue, 19 Jun 2018 10:39:50 -0500 Subject: [PATCH] mac80211: disable BHs/preemption in ieee80211_tx_control_port() On pre-emption enabled kernels the following print was being seen due to missing local_bh_disable/local_bh_enable calls. mac80211 assumes that pre-emption is disabled in the data path. BUG: using smp_processor_id() in preemptible [00000000] code: iwd/517 caller is __ieee80211_subif_start_xmit+0x144/0x210 [mac80211] [...] Call Trace: dump_stack+0x5c/0x80 check_preemption_disabled.cold.0+0x46/0x51 __ieee80211_subif_start_xmit+0x144/0x210 [mac80211] Fixes: 911806491425 ("mac80211: Add support for tx_control_port") Signed-off-by: Denis Kenzior [commit message rewrite, fixes tag] Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 44b5dfe8727d..fa1f1e63a264 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -4845,7 +4845,9 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev, skb_reset_network_header(skb); skb_reset_mac_header(skb); + local_bh_disable(); __ieee80211_subif_start_xmit(skb, skb->dev, flags); + local_bh_enable(); return 0; }