aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/patches-4.4/930-crashlog.patch
blob: bb97c90196d8b81c2d4fb3acab836a967da5d964 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
--- /dev/null
+++ b/include/linux/crashlog.h
@@ -0,0 +1,17 @@
+#ifndef __CRASHLOG_H
+#define __CRASHLOG_H
+
+#ifdef CONFIG_CRASHLOG
+void crashlog_init_bootmem(struct bootmem_data *bdata);
+void crashlog_init_memblock(phys_addr_t addr, phys_addr_t size);
+#else
+static inline void crashlog_init_bootmem(struct bootmem_data *bdata)
+{
+}
+
+static inline void crashlog_init_memblock(phys_addr_t addr, phys_addr_t size)
+{
+}
+#endif
+
+#endif
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1296,6 +1296,10 @@ config RELAY
 
 	  If unsure, say N.
 
+config CRASHLOG
+	bool "Crash logging"
+	depends on (!NO_BOOTMEM || HAVE_MEMBLOCK)
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -103,6 +103,7 @@ obj-$(CONFIG_TORTURE_TEST) += torture.o
 obj-$(CONFIG_MEMBARRIER) += membarrier.o
 
 obj-$(CONFIG_HAS_IOMEM) += memremap.o
+obj-$(CONFIG_CRASHLOG) += crashlog.o
 
 $(obj)/configs.o: $(obj)/config_data.h
 
--- /dev/null
+++ b/kernel/crashlog.c
@@ -0,0 +1,209 @@
+/*
+ * Crash information logger
+ * Copyright (C) 2010 Felix Fietkau <nbd@nbd.name>
+ *
+ * Based on ramoops.c
+ *   Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/bootmem.h>
+#include <linux/memblock.h>
+#include <linux/debugfs.h>
+#include <linux/crashlog.h>
+#include <linux/kmsg_dump.h>
+#include <linux/module.h>
+#include <linux/pfn.h>
+#include <linux/vmalloc.h>
+#include <asm/io.h>
+
+#define CRASHLOG_PAGES	4
+#define CRASHLOG_SIZE	(CRASHLOG_PAGES * PAGE_SIZE)
+#define CRASHLOG_MAGIC	0xa1eedead
+
+/*
+ * Start the log at 1M before the end of RAM, as some boot loaders like
+ * to use the end of the RAM for stack usage and other things
+ * If this fails, fall back to using the last part.
+ */
+#define CRASHLOG_OFFSET	(1024 * 1024)
+
+struct crashlog_data {
+	u32 magic;
+	u32 len;
+	u8 data[];
+};
+
+static struct debugfs_blob_wrapper crashlog_blob;
+static unsigned long crashlog_addr = 0;
+static struct crashlog_data *crashlog_buf;
+static struct kmsg_dumper dump;
+static bool first = true;
+
+extern struct list_head *crashlog_modules;
+
+static bool crashlog_set_addr(phys_addr_t addr, phys_addr_t size)
+{
+	/* Limit to lower 64 MB to avoid highmem */
+	phys_addr_t limit = 64 * 1024 * 1024;
+
+	if (crashlog_addr)
+		return false;
+
+	if (addr > limit)
+		return false;
+
+	if (addr + size > limit)
+		size = limit - addr;
+
+	crashlog_addr = addr + size - CRASHLOG_OFFSET;
+	return true;
+}
+
+#ifndef CONFIG_NO_BOOTMEM
+void __init crashlog_init_bootmem(bootmem_data_t *bdata)
+{
+	phys_addr_t start, end;
+
+	start = PFN_PHYS(bdata->node_low_pfn);
+	end = PFN_PHYS(bdata->node_min_pfn);
+	if (!crashlog_set_addr(start, end - start))
+		return;
+
+	if (reserve_bootmem(crashlog_addr, CRASHLOG_SIZE, BOOTMEM_EXCLUSIVE) < 0) {
+		printk("Crashlog failed to allocate RAM at address 0x%lx\n",
+		       crashlog_addr);
+		crashlog_addr = 0;
+	}
+}
+#endif
+
+#ifdef CONFIG_HAVE_MEMBLOCK
+void __init_memblock crashlog_init_memblock(phys_addr_t addr, phys_addr_t size)
+{
+	if (!crashlog_set_addr(addr, size))
+		return;
+
+	if (memblock_reserve(crashlog_addr, CRASHLOG_SIZE)) {
+		printk("Crashlog failed to allocate RAM at address 0x%lx\n",
+		       crashlog_addr);
+		crashlog_addr = 0;
+	}
+}
+#endif
+
+static void __init crashlog_copy(void)
+{
+	if (crashlog_buf->magic != CRASHLOG_MAGIC)
+		return;
+
+	if (!crashlog_buf->len || crashlog_buf->len >
+	    CRASHLOG_SIZE - sizeof(*crashlog_buf))
+		return;
+
+	crashlog_blob.size = crashlog_buf->len;
+	crashlog_blob.data = kmemdup(crashlog_buf->data,
+		crashlog_buf->len, GFP_KERNEL);
+
+	debugfs_create_blob("crashlog", 0700, NULL, &crashlog_blob);
+}
+
+static int get_maxlen(void)
+{
+	return CRASHLOG_SIZE - sizeof(*crashlog_buf) - crashlog_buf->len;
+}
+
+static void crashlog_printf(const char *fmt, ...)
+{
+	va_list args;
+	int len = get_maxlen();
+
+	if (!len)
+		return;
+
+	va_start(args, fmt);
+	crashlog_buf->len += vscnprintf(
+		&crashlog_buf->data[crashlog_buf->len],
+		len, fmt, args);
+	va_end(args);
+}
+
+static void crashlog_do_dump(struct kmsg_dumper *dumper,
+		enum kmsg_dump_reason reason)
+{
+	struct timeval tv;
+	struct module *m;
+	char *buf;
+	size_t len;
+
+	if (!first)
+		crashlog_printf("\n===================================\n");
+
+	do_gettimeofday(&tv);
+	crashlog_printf("Time: %lu.%lu\n",
+		(long)tv.tv_sec, (long)tv.tv_usec);
+
+	if (first) {
+		crashlog_printf("Modules:");
+		list_for_each_entry(m, crashlog_modules, list) {
+			crashlog_printf("\t%s@%p+%x", m->name,
+			m->module_core, m->core_size,
+			m->module_init, m->init_size);
+		}
+		crashlog_printf("\n");
+		first = false;
+	}
+
+	buf = (char *)&crashlog_buf->data[crashlog_buf->len];
+
+	kmsg_dump_get_buffer(dumper, true, buf, get_maxlen(), &len);
+
+	crashlog_buf->len += len;
+}
+
+
+int __init crashlog_init_fs(void)
+{
+	struct page *pages[CRASHLOG_PAGES];
+	pgprot_t prot;
+	int i;
+
+	if (!crashlog_addr) {
+		printk("No memory allocated for crashlog\n");
+		return -ENOMEM;
+	}
+
+	printk("Crashlog allocated RAM at address 0x%lx\n", (unsigned long) crashlog_addr);
+	for (i = 0; i < CRASHLOG_PAGES; i++)
+		pages[i] = pfn_to_page((crashlog_addr >> PAGE_SHIFT) + i);
+
+	prot = pgprot_writecombine(PAGE_KERNEL);
+	crashlog_buf = vmap(pages, CRASHLOG_PAGES, VM_MAP, prot);
+
+	crashlog_copy();
+
+	crashlog_buf->magic = CRASHLOG_MAGIC;
+	crashlog_buf->len = 0;
+
+	dump.max_reason = KMSG_DUMP_OOPS;
+	dump.dump = crashlog_do_dump;
+	kmsg_dump_register(&dump);
+
+	return 0;
+}
+module_init(crashlog_init_fs);
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -275,6 +275,9 @@ static void mod_update_bounds(struct mod
 #ifdef CONFIG_KGDB_KDB
 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
 #endif /* CONFIG_KGDB_KDB */
+#ifdef CONFIG_CRASHLOG
+struct list_head *crashlog_modules = &modules;
+#endif
 
 static void module_assert_mutex(void)
 {
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -19,6 +19,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/memblock.h>
+#include <linux/crashlog.h>
 
 #include <asm-generic/sections.h>
 #include <linux/io.h>
@@ -503,6 +504,8 @@ static void __init_memblock memblock_ins
 	memblock_set_region_node(rgn, nid);
 	type->cnt++;
 	type->total_size += size;
+	if (type == &memblock.memory)
+		crashlog_init_memblock(base, size);
 }
 
 /**
@@ -541,6 +544,8 @@ int __init_memblock memblock_add_range(s
 		type->regions[0].flags = flags;
 		memblock_set_region_node(&type->regions[0], nid);
 		type->total_size = size;
+		if (type == &memblock.memory)
+			crashlog_init_memblock(base, size);
 		return 0;
 	}
 repeat:
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -15,6 +15,7 @@
 #include <linux/export.h>
 #include <linux/kmemleak.h>
 #include <linux/range.h>
+#include <linux/crashlog.h>
 #include <linux/memblock.h>
 #include <linux/bug.h>
 #include <linux/io.h>
@@ -177,6 +178,7 @@ static unsigned long __init free_all_boo
 	if (!bdata->node_bootmem_map)
 		return 0;
 
+	crashlog_init_bootmem(bdata);
 	map = bdata->node_bootmem_map;
 	start = bdata->node_min_pfn;
 	end = bdata->node_low_pfn;