9640cd4757fe38bad55c2f2cacaf37574fed0289
[oweals/openwrt.git] /
1 From 0254e953537c92df3e7d0176f401a211e944fd61 Mon Sep 17 00:00:00 2001
2 From: Guenter Roeck <linux@roeck-us.net>
3 Date: Sun, 3 Jan 2016 15:11:58 -0800
4 Subject: watchdog: Drop pointer to watchdog device from struct watchdog_device
5
6 The lifetime of the watchdog device pointer is different from the lifetime
7 of its character device. Remove it entirely to avoid race conditions.
8
9 Signed-off-by: Guenter Roeck <linux@roeck-us.net>
10 Signed-off-by: Guenter Roeck <linux@roeck-us.net>
11 Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
12 ---
13  Documentation/watchdog/watchdog-kernel-api.txt | 2 --
14  drivers/watchdog/watchdog_core.c               | 8 ++++----
15  drivers/watchdog/watchdog_dev.c                | 9 ++++-----
16  include/linux/watchdog.h                       | 2 --
17  4 files changed, 8 insertions(+), 13 deletions(-)
18
19 --- a/Documentation/watchdog/watchdog-kernel-api.txt
20 +++ b/Documentation/watchdog/watchdog-kernel-api.txt
21 @@ -44,7 +44,6 @@ The watchdog device structure looks like
22  
23  struct watchdog_device {
24         int id;
25 -       struct device *dev;
26         struct device *parent;
27         const struct watchdog_info *info;
28         const struct watchdog_ops *ops;
29 @@ -65,7 +64,6 @@ It contains following fields:
30    /dev/watchdog0 cdev (dynamic major, minor 0) as well as the old
31    /dev/watchdog miscdev. The id is set automatically when calling
32    watchdog_register_device.
33 -* dev: device under the watchdog class (created by watchdog_register_device).
34  * parent: set this to the parent device (or NULL) before calling
35    watchdog_register_device.
36  * info: a pointer to a watchdog_info structure. This structure gives some
37 --- a/drivers/watchdog/watchdog_core.c
38 +++ b/drivers/watchdog/watchdog_core.c
39 @@ -249,8 +249,8 @@ static int __watchdog_register_device(st
40  
41                 ret = register_reboot_notifier(&wdd->reboot_nb);
42                 if (ret) {
43 -                       dev_err(wdd->dev, "Cannot register reboot notifier (%d)\n",
44 -                               ret);
45 +                       pr_err("watchdog%d: Cannot register reboot notifier (%d)\n",
46 +                              wdd->id, ret);
47                         watchdog_dev_unregister(wdd);
48                         ida_simple_remove(&watchdog_ida, wdd->id);
49                         return ret;
50 @@ -262,8 +262,8 @@ static int __watchdog_register_device(st
51  
52                 ret = register_restart_handler(&wdd->restart_nb);
53                 if (ret)
54 -                       dev_warn(wdd->dev, "Cannot register restart handler (%d)\n",
55 -                                ret);
56 +                       pr_warn("watchog%d: Cannot register restart handler (%d)\n",
57 +                               wdd->id, ret);
58         }
59  
60         return 0;
61 --- a/drivers/watchdog/watchdog_dev.c
62 +++ b/drivers/watchdog/watchdog_dev.c
63 @@ -143,7 +143,8 @@ static int watchdog_stop(struct watchdog
64                 return 0;
65  
66         if (test_bit(WDOG_NO_WAY_OUT, &wdd->status)) {
67 -               dev_info(wdd->dev, "nowayout prevents watchdog being stopped!\n");
68 +               pr_info("watchdog%d: nowayout prevents watchdog being stopped!\n",
69 +                       wdd->id);
70                 return -EBUSY;
71         }
72  
73 @@ -604,7 +605,7 @@ static int watchdog_release(struct inode
74  
75         /* If the watchdog was not stopped, send a keepalive ping */
76         if (err < 0) {
77 -               dev_crit(wdd->dev, "watchdog did not stop!\n");
78 +               pr_crit("watchdog%d: watchdog did not stop!\n", wdd->id);
79                 watchdog_ping(wdd);
80         }
81  
82 @@ -750,7 +751,6 @@ int watchdog_dev_register(struct watchdo
83                 watchdog_cdev_unregister(wdd);
84                 return PTR_ERR(dev);
85         }
86 -       wdd->dev = dev;
87  
88         return ret;
89  }
90 @@ -765,8 +765,7 @@ int watchdog_dev_register(struct watchdo
91  
92  void watchdog_dev_unregister(struct watchdog_device *wdd)
93  {
94 -       device_destroy(&watchdog_class, wdd->dev->devt);
95 -       wdd->dev = NULL;
96 +       device_destroy(&watchdog_class, wdd->wd_data->cdev.dev);
97         watchdog_cdev_unregister(wdd);
98  }
99  
100 --- a/include/linux/watchdog.h
101 +++ b/include/linux/watchdog.h
102 @@ -55,7 +55,6 @@ struct watchdog_ops {
103  /** struct watchdog_device - The structure that defines a watchdog device
104   *
105   * @id:                The watchdog's ID. (Allocated by watchdog_register_device)
106 - * @dev:       The device for our watchdog
107   * @parent:    The parent bus device
108   * @info:      Pointer to a watchdog_info structure.
109   * @ops:       Pointer to the list of watchdog operations.
110 @@ -82,7 +81,6 @@ struct watchdog_ops {
111   */
112  struct watchdog_device {
113         int id;
114 -       struct device *dev;
115         struct device *parent;
116         const struct watchdog_info *info;
117         const struct watchdog_ops *ops;