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From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date: Sun, 8 Jan 2023 22:13:23 +0100
Subject: [PATCH] wifi: rtw88: Use rtw_iterate_vifs() for
 rtw_vif_watch_dog_iter()
References: bsc#1012628
Patch-mainline: 6.2.3
Git-commit: 313f6dc7c5ed723d0c5691553eff4c0090f16bb8

[ Upstream commit 313f6dc7c5ed723d0c5691553eff4c0090f16bb8 ]

USB and (upcoming) SDIO support may sleep in the read/write handlers.
Make rtw_watch_dog_work() use rtw_iterate_vifs() to prevent "scheduling
while atomic" or "Voluntary context switch within RCU read-side
critical section!" warnings when accessing the registers using an SDIO
card (which is where this issue has been spotted in the real world but
it also affects USB cards).

Fixes: 78d5bf925f30 ("wifi: rtw88: iterate over vif/sta list non-atomically")
Suggested-by: Ping-Ke Shih <pkshih@realtek.com>
Reviewed-by: Ping-Ke Shih <pkshih@realtek.com>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230108211324.442823-3-martin.blumenstingl@googlemail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/net/wireless/realtek/rtw88/main.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/main.c b/drivers/net/wireless/realtek/rtw88/main.c
index 888427cf..b2e78737 100644
--- a/drivers/net/wireless/realtek/rtw88/main.c
+++ b/drivers/net/wireless/realtek/rtw88/main.c
@@ -241,8 +241,10 @@ static void rtw_watch_dog_work(struct work_struct *work)
 	rtw_phy_dynamic_mechanism(rtwdev);
 
 	data.rtwdev = rtwdev;
-	/* use atomic version to avoid taking local->iflist_mtx mutex */
-	rtw_iterate_vifs_atomic(rtwdev, rtw_vif_watch_dog_iter, &data);
+	/* rtw_iterate_vifs internally uses an atomic iterator which is needed
+	 * to avoid taking local->iflist_mtx mutex
+	 */
+	rtw_iterate_vifs(rtwdev, rtw_vif_watch_dog_iter, &data);
 
 	/* fw supports only one station associated to enter lps, if there are
 	 * more than two stations associated to the AP, then we can not enter
-- 
2.35.3