This is a note to let you know that I've just added the patch titled
wifi: mac80211: Serialize ieee80211_handle_wake_tx_queue()
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-mac80211-serialize-ieee80211_handle_wake_tx_queue.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 007ae9b268ba7553e479608cf9735d3c4672a2ab Mon Sep 17 00:00:00 2001
From: Alexander Wetzel <alexander@xxxxxxxxxxxxxx>
Date: Tue, 14 Mar 2023 22:11:22 +0100
Subject: wifi: mac80211: Serialize ieee80211_handle_wake_tx_queue()
From: Alexander Wetzel <alexander@xxxxxxxxxxxxxx>
commit 007ae9b268ba7553e479608cf9735d3c4672a2ab upstream.
ieee80211_handle_wake_tx_queue must not run concurrent multiple times.
It calls ieee80211_txq_schedule_start() and the drivers migrated to iTXQ
do not expect overlapping drv_tx() calls.
This fixes 'c850e31f79f0 ("wifi: mac80211: add internal handler for
wake_tx_queue")', which introduced ieee80211_handle_wake_tx_queue.
Drivers started to use it with 'a790cc3a4fad ("wifi: mac80211: add
wake_tx_queue callback to drivers")'.
But only after fixing an independent bug with
'4444bc2116ae ("wifi: mac80211: Proper mark iTXQs for resumption")'
problematic concurrent calls really happened and exposed the initial
issue.
Fixes: c850e31f79f0 ("wifi: mac80211: add internal handler for wake_tx_queue")
Reported-by: Thomas Mann <rauchwolke@xxxxxxx>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217119
Link: https://lore.kernel.org/r/b8efebc6-4399-d0b8-b2a0-66843314616b@xxxxxxxxxxxxx/
Link: https://lore.kernel.org/r/b7445607128a6b9ed7c17fcdcf3679bfaf4aaea.camel@xxxxxxxxxxxxxxxx>
CC: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Alexander Wetzel <alexander@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230314211122.111688-1-alexander@xxxxxxxxxxxxxx
[add missing spin_lock_init() noticed by Felix]
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mac80211/ieee80211_i.h | 3 +++
net/mac80211/main.c | 2 ++
net/mac80211/util.c | 3 +++
3 files changed, 8 insertions(+)
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1285,6 +1285,9 @@ struct ieee80211_local {
struct list_head active_txqs[IEEE80211_NUM_ACS];
u16 schedule_round[IEEE80211_NUM_ACS];
+ /* serializes ieee80211_handle_wake_tx_queue */
+ spinlock_t handle_wake_tx_queue_lock;
+
u16 airtime_flags;
u32 aql_txq_limit_low[IEEE80211_NUM_ACS];
u32 aql_txq_limit_high[IEEE80211_NUM_ACS];
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -802,6 +802,8 @@ struct ieee80211_hw *ieee80211_alloc_hw_
local->aql_threshold = IEEE80211_AQL_THRESHOLD;
atomic_set(&local->aql_total_pending_airtime, 0);
+ spin_lock_init(&local->handle_wake_tx_queue_lock);
+
INIT_LIST_HEAD(&local->chanctx_list);
mutex_init(&local->chanctx_mtx);
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -314,6 +314,8 @@ void ieee80211_handle_wake_tx_queue(stru
struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
struct ieee80211_txq *queue;
+ spin_lock(&local->handle_wake_tx_queue_lock);
+
/* Use ieee80211_next_txq() for airtime fairness accounting */
ieee80211_txq_schedule_start(hw, txq->ac);
while ((queue = ieee80211_next_txq(hw, txq->ac))) {
@@ -321,6 +323,7 @@ void ieee80211_handle_wake_tx_queue(stru
ieee80211_return_txq(hw, queue, false);
}
ieee80211_txq_schedule_end(hw, txq->ac);
+ spin_unlock(&local->handle_wake_tx_queue_lock);
}
EXPORT_SYMBOL(ieee80211_handle_wake_tx_queue);
Patches currently in stable-queue which might be from alexander@xxxxxxxxxxxxxx are
queue-6.2/wifi-mac80211-serialize-ieee80211_handle_wake_tx_queue.patch
