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From 0602088b10a7c0b4e044a810678ef93d7cc5bf48 Mon Sep 17 00:00:00 2001
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Date: Wed, 20 Jun 2018 11:54:53 +0800
Subject: [PATCH] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller()
Git-commit: 0602088b10a7c0b4e044a810678ef93d7cc5bf48
Patch-mainline: v4.18-rc7
References: bsc#1051510

The driver may sleep with holding a spinlock.
The function call paths (from bottom to top) in Linux-4.16.7 are:

[FUNC] msleep
drivers/usb/gadget/udc/r8a66597-udc.c, 839:
		msleep in init_controller
drivers/usb/gadget/udc/r8a66597-udc.c, 96:
		init_controller in r8a66597_usb_disconnect
drivers/usb/gadget/udc/r8a66597-udc.c, 93:
		spin_lock in r8a66597_usb_disconnect

[FUNC] msleep
drivers/usb/gadget/udc/r8a66597-udc.c, 835:
		msleep in init_controller
drivers/usb/gadget/udc/r8a66597-udc.c, 96:
		init_controller in r8a66597_usb_disconnect
drivers/usb/gadget/udc/r8a66597-udc.c, 93:
		spin_lock in r8a66597_usb_disconnect

To fix these bugs, msleep() is replaced with mdelay().

This bug is found by my static analysis tool (DSAC-2) and checked by
my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/gadget/udc/r8a66597-udc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/udc/r8a66597-udc.c b/drivers/usb/gadget/udc/r8a66597-udc.c
index a3ecce62662b..24ee9867964b 100644
--- a/drivers/usb/gadget/udc/r8a66597-udc.c
+++ b/drivers/usb/gadget/udc/r8a66597-udc.c
@@ -832,11 +832,11 @@ static void init_controller(struct r8a66597 *r8a66597)
 
 		r8a66597_bset(r8a66597, XCKE, SYSCFG0);
 
-		msleep(3);
+		mdelay(3);
 
 		r8a66597_bset(r8a66597, PLLC, SYSCFG0);
 
-		msleep(1);
+		mdelay(1);
 
 		r8a66597_bset(r8a66597, SCKE, SYSCFG0);
 
-- 
2.18.0