[PATCH ath-next 01/15] wifi: ath12k: fix a possible dead lock caused by ab->base_lock

[Baochen Qiang]

spin_lock/spin_unlock are used in ath12k_reg_chan_list_event
to acquire/release ab->base_lock. For now this is safe because
that function is only called in soft IRQ context.

But ath12k_reg_chan_list_event() will be called from process
context in an upcoming patch, and this can result in a deadlock
if ab->base_lock is acquired in process context and then soft
IRQ occurs on the same CPU and tries to acquire that lock.

Fix it by using spin_lock_bh and spin_unlock_bh instead.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Signed-off-by: Baochen Qiang <quic_bqiang@xxxxxxxxxxx>
---
 drivers/net/wireless/ath/ath12k/wmi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c
index ea303dca38b51f98399079cd3ac06a48fd9cc025..256e05e28afdbee8267bd2ab25bb47cba4530e96 100644
--- a/drivers/net/wireless/ath/ath12k/wmi.c
+++ b/drivers/net/wireless/ath/ath12k/wmi.c
@@ -6194,7 +6194,7 @@ static int ath12k_reg_chan_list_event(struct ath12k_base *ab, struct sk_buff *sk
 		goto fallback;
 	}
 
-	spin_lock(&ab->base_lock);
+	spin_lock_bh(&ab->base_lock);
 	if (test_bit(ATH12K_FLAG_REGISTERED, &ab->dev_flags)) {
 		/* Once mac is registered, ar is valid and all CC events from
 		 * fw is considered to be received due to user requests
@@ -6218,7 +6218,7 @@ static int ath12k_reg_chan_list_event(struct ath12k_base *ab, struct sk_buff *sk
 		ab->default_regd[pdev_idx] = regd;
 	}
 	ab->dfs_region = reg_info->dfs_region;
-	spin_unlock(&ab->base_lock);
+	spin_unlock_bh(&ab->base_lock);
 
 	goto mem_free;
 

-- 
2.34.1