[PATCH] rtlwifi: rtl8192cu: Fix WARNING when calling local_irq_restore() with interrupts enabled

Syzbot reports the following WARNING:

[200~raw_local_irq_restore() called with IRQs enabled
WARNING: CPU: 1 PID: 1206 at kernel/locking/irqflag-debug.c:10
   warn_bogus_irq_restore+0x1d/0x20 kernel/locking/irqflag-debug.c:10

Hardware initialization for the rtl8188cu can run for as long as 350 ms,
and the routine may be called with interrupts disabled. To avoid locking
the machine for this long, the current routine saves the interrupt flags
and enables local interrupts. The problem is that it restores the flags
at the end without disabling local interrupts first.

This patch fixes commit a53268be0cb9 ("rtlwifi: rtl8192cu: Fix too long
disable of IRQs").

Reported-by: syzbot+cce1ee31614c171f5595@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Fixes: a53268be0cb9 ("rtlwifi: rtl8192cu: Fix too long disable of IRQs")
Signed-off-by: Larry Finger <redacted>
---
 drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c
index 6312fddd9c00..eaba66113328 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192cu/hw.c

@@ -1000,6 +1000,7 @@ int rtl92cu_hw_init(struct ieee80211_hw *hw)
 	_initpabias(hw);
 	rtl92c_dm_init(hw);
 exit:
+	local_irq_disable();
 	local_irq_restore(flags);
 	return err;
 }

-- 
2.34.1

Larry Finger [off-list ref] wrote:

Syzbot reports the following WARNING:

[200~raw_local_irq_restore() called with IRQs enabled
WARNING: CPU: 1 PID: 1206 at kernel/locking/irqflag-debug.c:10
   warn_bogus_irq_restore+0x1d/0x20 kernel/locking/irqflag-debug.c:10

Hardware initialization for the rtl8188cu can run for as long as 350 ms,
and the routine may be called with interrupts disabled. To avoid locking
the machine for this long, the current routine saves the interrupt flags
and enables local interrupts. The problem is that it restores the flags
at the end without disabling local interrupts first.

This patch fixes commit a53268be0cb9 ("rtlwifi: rtl8192cu: Fix too long
disable of IRQs").

Reported-by: syzbot+cce1ee31614c171f5595@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Fixes: a53268be0cb9 ("rtlwifi: rtl8192cu: Fix too long disable of IRQs")
Signed-off-by: Larry Finger <redacted>

Patch applied to wireless-drivers-next.git, thanks.

8b144dedb928 rtlwifi: rtl8192cu: Fix WARNING when calling local_irq_restore() with interrupts enabled

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20211215171105.20623-1-Larry.Finger@lwfinger.net/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches