releases/4.4.154/usb-gadget-r8a66597-fix-two-possible-sleep-in-atomic-context-bugs-in-init_controller.patch

   1 From foo@baz Tue Aug 28 16:10:37 CEST 2018
   2 From: Jia-Ju Bai <baijiaju1990@gmail.com>
   3 Date: Wed, 20 Jun 2018 11:54:53 +0800
   4 Subject: usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller()
   5
   6 From: Jia-Ju Bai <baijiaju1990@gmail.com>
   7
   8 [ Upstream commit 0602088b10a7c0b4e044a810678ef93d7cc5bf48 ]
   9
  10 The driver may sleep with holding a spinlock.
  11 The function call paths (from bottom to top) in Linux-4.16.7 are:
  12
  13 [FUNC] msleep
  14 drivers/usb/gadget/udc/r8a66597-udc.c, 839:
  15                 msleep in init_controller
  16 drivers/usb/gadget/udc/r8a66597-udc.c, 96:
  17                 init_controller in r8a66597_usb_disconnect
  18 drivers/usb/gadget/udc/r8a66597-udc.c, 93:
  19                 spin_lock in r8a66597_usb_disconnect
  20
  21 [FUNC] msleep
  22 drivers/usb/gadget/udc/r8a66597-udc.c, 835:
  23                 msleep in init_controller
  24 drivers/usb/gadget/udc/r8a66597-udc.c, 96:
  25                 init_controller in r8a66597_usb_disconnect
  26 drivers/usb/gadget/udc/r8a66597-udc.c, 93:
  27                 spin_lock in r8a66597_usb_disconnect
  28
  29 To fix these bugs, msleep() is replaced with mdelay().
  30
  31 This bug is found by my static analysis tool (DSAC-2) and checked by
  32 my code review.
  33
  34 Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
  35 Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
  36 Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
  37 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  38 ---
  39  drivers/usb/gadget/udc/r8a66597-udc.c |    4 ++--
  40  1 file changed, 2 insertions(+), 2 deletions(-)
  41
  42 --- a/drivers/usb/gadget/udc/r8a66597-udc.c
  43 +++ b/drivers/usb/gadget/udc/r8a66597-udc.c
  44 @@ -835,11 +835,11 @@ static void init_controller(struct r8a66
  45
  46                 r8a66597_bset(r8a66597, XCKE, SYSCFG0);
  47
  48 -               msleep(3);
  49 +               mdelay(3);
  50
  51                 r8a66597_bset(r8a66597, PLLC, SYSCFG0);
  52
  53 -               msleep(1);
  54 +               mdelay(1);
  55
  56                 r8a66597_bset(r8a66597, SCKE, SYSCFG0);
  57