diff mbox series

[5.7,085/376] ath11k: Avoid mgmt tx count underflow

Message ID 20200619141714.368063613@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman June 19, 2020, 2:30 p.m. UTC 
From: Sriram R <srirrama@codeaurora.org>

[ Upstream commit 800113ff4b1d277c2b66ffc04d4d38f202a0d187 ]

The mgmt tx count reference is incremented/decremented on every mgmt tx and on
tx completion event from firmware.
In case of an unexpected mgmt tx completion event from firmware,
the counter would underflow. Avoid this by decrementing
only when the tx count is greater than 0.

Signed-off-by: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1585567028-9242-1-git-send-email-srirrama@codeaurora.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/ath/ath11k/wmi.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath11k/wmi.c b/drivers/net/wireless/ath/ath11k/wmi.c
index 6fec62846279..73beca6d6b5f 100644
--- a/drivers/net/wireless/ath/ath11k/wmi.c
+++ b/drivers/net/wireless/ath/ath11k/wmi.c
@@ -3740,8 +3740,9 @@  static int wmi_process_mgmt_tx_comp(struct ath11k *ar, u32 desc_id,
 
 	ieee80211_tx_status_irqsafe(ar->hw, msdu);
 
-	WARN_ON_ONCE(atomic_read(&ar->num_pending_mgmt_tx) == 0);
-	atomic_dec(&ar->num_pending_mgmt_tx);
+	/* WARN when we received this event without doing any mgmt tx */
+	if (atomic_dec_if_positive(&ar->num_pending_mgmt_tx) < 0)
+		WARN_ON_ONCE(1);
 
 	return 0;
 }