diff --git a/0004-mac80211-disable-BHs-preemption-in-ieee80211_tx_cont.patch b/0004-mac80211-disable-BHs-preemption-in-ieee80211_tx_cont.patch new file mode 100644 index 0000000..de3385e --- /dev/null +++ b/0004-mac80211-disable-BHs-preemption-in-ieee80211_tx_cont.patch @@ -0,0 +1,46 @@ +From 32a72bee7a275f47c235fdb36249703c892ce8d8 Mon Sep 17 00:00:00 2001 +Message-Id: <32a72bee7a275f47c235fdb36249703c892ce8d8.1531335939.git.jan.steffens@gmail.com> +In-Reply-To: +References: +From: Denis Kenzior +Date: Tue, 19 Jun 2018 10:39:50 -0500 +Subject: [PATCH 4/4] 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 05a265cd573d..7404a5114597 100644 +--- a/net/mac80211/tx.c ++++ b/net/mac80211/tx.c +@@ -4800,7 +4800,9 @@ 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; + } +-- +2.18.0 +