blob: 10ea71905c1fbbb8a9582737e05f78fefa86012e [file] [log] [blame]
Andi Kleencae681f2009-09-16 11:50:17 +02001/* Inject a hwpoison memory failure on a arbitary pfn */
2#include <linux/module.h>
3#include <linux/debugfs.h>
4#include <linux/kernel.h>
5#include <linux/mm.h>
Wu Fengguang31d3d342009-12-16 12:19:59 +01006#include <linux/swap.h>
7#include <linux/pagemap.h>
Wu Fengguang7c116f22009-12-16 12:19:59 +01008#include "internal.h"
Andi Kleencae681f2009-09-16 11:50:17 +02009
Wu Fengguang847ce402009-12-16 12:19:58 +010010static struct dentry *hwpoison_dir;
Andi Kleencae681f2009-09-16 11:50:17 +020011
12static int hwpoison_inject(void *data, u64 val)
13{
Wu Fengguang31d3d342009-12-16 12:19:59 +010014 unsigned long pfn = val;
15 struct page *p;
16 int err;
17
Andi Kleencae681f2009-09-16 11:50:17 +020018 if (!capable(CAP_SYS_ADMIN))
19 return -EPERM;
Wu Fengguang31d3d342009-12-16 12:19:59 +010020
Andi Kleen0d57eb82009-12-16 12:20:01 +010021 if (!hwpoison_filter_enable)
22 goto inject;
Wu Fengguang31d3d342009-12-16 12:19:59 +010023 if (!pfn_valid(pfn))
24 return -ENXIO;
25
26 p = pfn_to_page(pfn);
27 /*
28 * This implies unable to support free buddy pages.
29 */
30 if (!get_page_unless_zero(p))
31 return 0;
32
33 if (!PageLRU(p))
Andi Kleenfacb6012009-12-16 12:20:00 +010034 shake_page(p, 0);
Wu Fengguang31d3d342009-12-16 12:19:59 +010035 /*
36 * This implies unable to support non-LRU pages.
37 */
38 if (!PageLRU(p))
39 return 0;
40
41 /*
42 * do a racy check with elevated page count, to make sure PG_hwpoison
43 * will only be set for the targeted owner (or on a free page).
44 * We temporarily take page lock for try_get_mem_cgroup_from_page().
45 * __memory_failure() will redo the check reliably inside page lock.
46 */
47 lock_page(p);
48 err = hwpoison_filter(p);
49 unlock_page(p);
50 if (err)
51 return 0;
52
Andi Kleen0d57eb82009-12-16 12:20:01 +010053inject:
Wu Fengguang31d3d342009-12-16 12:19:59 +010054 printk(KERN_INFO "Injecting memory failure at pfn %lx\n", pfn);
55 return __memory_failure(pfn, 18, MF_COUNT_INCREASED);
Andi Kleencae681f2009-09-16 11:50:17 +020056}
57
Wu Fengguang847ce402009-12-16 12:19:58 +010058static int hwpoison_unpoison(void *data, u64 val)
59{
60 if (!capable(CAP_SYS_ADMIN))
61 return -EPERM;
62
63 return unpoison_memory(val);
64}
65
Andi Kleencae681f2009-09-16 11:50:17 +020066DEFINE_SIMPLE_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
Wu Fengguang847ce402009-12-16 12:19:58 +010067DEFINE_SIMPLE_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n");
Andi Kleencae681f2009-09-16 11:50:17 +020068
69static void pfn_inject_exit(void)
70{
71 if (hwpoison_dir)
72 debugfs_remove_recursive(hwpoison_dir);
73}
74
75static int pfn_inject_init(void)
76{
Wu Fengguang847ce402009-12-16 12:19:58 +010077 struct dentry *dentry;
78
Andi Kleencae681f2009-09-16 11:50:17 +020079 hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
80 if (hwpoison_dir == NULL)
81 return -ENOMEM;
Wu Fengguang847ce402009-12-16 12:19:58 +010082
83 /*
84 * Note that the below poison/unpoison interfaces do not involve
85 * hardware status change, hence do not require hardware support.
86 * They are mainly for testing hwpoison in software level.
87 */
88 dentry = debugfs_create_file("corrupt-pfn", 0600, hwpoison_dir,
Andi Kleencae681f2009-09-16 11:50:17 +020089 NULL, &hwpoison_fops);
Wu Fengguang847ce402009-12-16 12:19:58 +010090 if (!dentry)
91 goto fail;
92
93 dentry = debugfs_create_file("unpoison-pfn", 0600, hwpoison_dir,
94 NULL, &unpoison_fops);
95 if (!dentry)
96 goto fail;
97
Haicheng Li1bfe5fe2009-12-16 12:19:59 +010098 dentry = debugfs_create_u32("corrupt-filter-enable", 0600,
99 hwpoison_dir, &hwpoison_filter_enable);
100 if (!dentry)
101 goto fail;
102
Wu Fengguang7c116f22009-12-16 12:19:59 +0100103 dentry = debugfs_create_u32("corrupt-filter-dev-major", 0600,
104 hwpoison_dir, &hwpoison_filter_dev_major);
105 if (!dentry)
106 goto fail;
107
108 dentry = debugfs_create_u32("corrupt-filter-dev-minor", 0600,
109 hwpoison_dir, &hwpoison_filter_dev_minor);
110 if (!dentry)
111 goto fail;
112
Wu Fengguang478c5ff2009-12-16 12:19:59 +0100113 dentry = debugfs_create_u64("corrupt-filter-flags-mask", 0600,
114 hwpoison_dir, &hwpoison_filter_flags_mask);
115 if (!dentry)
116 goto fail;
117
118 dentry = debugfs_create_u64("corrupt-filter-flags-value", 0600,
119 hwpoison_dir, &hwpoison_filter_flags_value);
120 if (!dentry)
121 goto fail;
122
Andi Kleen4fd466e2009-12-16 12:19:59 +0100123#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
124 dentry = debugfs_create_u64("corrupt-filter-memcg", 0600,
125 hwpoison_dir, &hwpoison_filter_memcg);
126 if (!dentry)
127 goto fail;
128#endif
129
Andi Kleencae681f2009-09-16 11:50:17 +0200130 return 0;
Wu Fengguang847ce402009-12-16 12:19:58 +0100131fail:
132 pfn_inject_exit();
133 return -ENOMEM;
Andi Kleencae681f2009-09-16 11:50:17 +0200134}
135
136module_init(pfn_inject_init);
137module_exit(pfn_inject_exit);
138MODULE_LICENSE("GPL");