From 9be550ee43919b070bcd77f9228bdbbbc073245b Mon Sep 17 00:00:00 2001
From: Pavel Skripkin <paskripkin@gmail.com>
Date: Wed, 21 Jul 2021 22:34:36 +0300
Subject: [PATCH] staging: rtl8712: get rid of flush_scheduled_work
Git-commit: 9be550ee43919b070bcd77f9228bdbbbc073245b
Patch-mainline: v5.14-rc5
References: git-fixes

This patch is preparation for following patch for error handling
refactoring.

flush_scheduled_work() takes (wq_completion)events lock and
it can lead to deadlock when r871xu_dev_remove() is called from workqueue.
To avoid deadlock sutiation we can change flush_scheduled_work() call to
flush_work() call for all possibly scheduled works in this driver,
since next patch adds device_release_driver() in case of fw load failure.

Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/6e028b4c457eeb7156c76c6ea3cdb3cb0207c7e1.1626895918.git.paskripkin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/staging/rtl8712/rtl8712_led.c     | 8 ++++++++
 drivers/staging/rtl8712/rtl871x_led.h     | 1 +
 drivers/staging/rtl8712/rtl871x_pwrctrl.c | 8 ++++++++
 drivers/staging/rtl8712/rtl871x_pwrctrl.h | 1 +
 drivers/staging/rtl8712/usb_intf.c        | 3 ++-
 5 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8712/rtl8712_led.c b/drivers/staging/rtl8712/rtl8712_led.c
index 5901026949f2..d5fc9026b036 100644
--- a/drivers/staging/rtl8712/rtl8712_led.c
+++ b/drivers/staging/rtl8712/rtl8712_led.c
@@ -1820,3 +1820,11 @@ void LedControl871x(struct _adapter *padapter, enum LED_CTL_MODE LedAction)
 		break;
 	}
 }
+
+void r8712_flush_led_works(struct _adapter *padapter)
+{
+	struct led_priv *pledpriv = &padapter->ledpriv;
+
+	flush_work(&pledpriv->SwLed0.BlinkWorkItem);
+	flush_work(&pledpriv->SwLed1.BlinkWorkItem);
+}
diff --git a/drivers/staging/rtl8712/rtl871x_led.h b/drivers/staging/rtl8712/rtl871x_led.h
index ee19c873cf01..2f0768132ad8 100644
--- a/drivers/staging/rtl8712/rtl871x_led.h
+++ b/drivers/staging/rtl8712/rtl871x_led.h
@@ -112,6 +112,7 @@ struct led_priv {
 void r8712_InitSwLeds(struct _adapter *padapter);
 void r8712_DeInitSwLeds(struct _adapter *padapter);
 void LedControl871x(struct _adapter *padapter, enum LED_CTL_MODE LedAction);
+void r8712_flush_led_works(struct _adapter *padapter);
 
 #endif
 
diff --git a/drivers/staging/rtl8712/rtl871x_pwrctrl.c b/drivers/staging/rtl8712/rtl871x_pwrctrl.c
index 23cff43437e2..cd6d9ff0bebc 100644
--- a/drivers/staging/rtl8712/rtl871x_pwrctrl.c
+++ b/drivers/staging/rtl8712/rtl871x_pwrctrl.c
@@ -224,3 +224,11 @@ void r8712_unregister_cmd_alive(struct _adapter *padapter)
 	}
 	mutex_unlock(&pwrctrl->mutex_lock);
 }
+
+void r8712_flush_rwctrl_works(struct _adapter *padapter)
+{
+	struct pwrctrl_priv *pwrctrl = &padapter->pwrctrlpriv;
+
+	flush_work(&pwrctrl->SetPSModeWorkItem);
+	flush_work(&pwrctrl->rpwm_workitem);
+}
diff --git a/drivers/staging/rtl8712/rtl871x_pwrctrl.h b/drivers/staging/rtl8712/rtl871x_pwrctrl.h
index bf6623cfaf27..b35b9c7920eb 100644
--- a/drivers/staging/rtl8712/rtl871x_pwrctrl.h
+++ b/drivers/staging/rtl8712/rtl871x_pwrctrl.h
@@ -108,5 +108,6 @@ void r8712_cpwm_int_hdl(struct _adapter *padapter,
 void r8712_set_ps_mode(struct _adapter *padapter, uint ps_mode,
 			uint smart_ps);
 void r8712_set_rpwm(struct _adapter *padapter, u8 val8);
+void r8712_flush_rwctrl_works(struct _adapter *padapter);
 
 #endif  /* __RTL871X_PWRCTRL_H_ */
diff --git a/drivers/staging/rtl8712/usb_intf.c b/drivers/staging/rtl8712/usb_intf.c
index 2434b13c8b12..643f21eb1128 100644
--- a/drivers/staging/rtl8712/usb_intf.c
+++ b/drivers/staging/rtl8712/usb_intf.c
@@ -606,7 +606,8 @@ static void r871xu_dev_remove(struct usb_interface *pusb_intf)
 			padapter->surprise_removed = true;
 		if (pnetdev->reg_state != NETREG_UNINITIALIZED)
 			unregister_netdev(pnetdev); /* will call netdev_close() */
-		flush_scheduled_work();
+		r8712_flush_rwctrl_works(padapter);
+		r8712_flush_led_works(padapter);
 		udelay(1);
 		/* Stop driver mlme relation timer */
 		r8712_stop_drv_timers(padapter);
-- 
2.26.2