# CONFIG_CPU_FREQ is not set
# CONFIG_CPU_IDLE is not set
# CONFIG_CRAMFS is not set
+CONFIG_CRASHLOG=y
# CONFIG_CRASH_DUMP is not set
# CONFIG_CRC16 is not set
CONFIG_CRC32=y
# CONFIG_CPU_FREQ is not set
# CONFIG_CPU_IDLE is not set
# CONFIG_CRAMFS is not set
+CONFIG_CRASHLOG=y
# CONFIG_CRASH_DUMP is not set
# CONFIG_CRC16 is not set
CONFIG_CRC32=y
--- /dev/null
+--- /dev/null
++++ b/include/linux/kmsg_dump.h
+@@ -0,0 +1,44 @@
++/*
++ * linux/include/kmsg_dump.h
++ *
++ * Copyright (C) 2009 Net Insight AB
++ *
++ * Author: Simon Kagstrom <simon.kagstrom@netinsight.net>
++ *
++ * This file is subject to the terms and conditions of the GNU General Public
++ * License. See the file COPYING in the main directory of this archive
++ * for more details.
++ */
++#ifndef _LINUX_KMSG_DUMP_H
++#define _LINUX_KMSG_DUMP_H
++
++#include <linux/list.h>
++
++enum kmsg_dump_reason {
++ KMSG_DUMP_OOPS,
++ KMSG_DUMP_PANIC,
++};
++
++/**
++ * struct kmsg_dumper - kernel crash message dumper structure
++ * @dump: The callback which gets called on crashes. The buffer is passed
++ * as two sections, where s1 (length l1) contains the older
++ * messages and s2 (length l2) contains the newer.
++ * @list: Entry in the dumper list (private)
++ * @registered: Flag that specifies if this is already registered
++ */
++struct kmsg_dumper {
++ void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
++ const char *s1, unsigned long l1,
++ const char *s2, unsigned long l2);
++ struct list_head list;
++ int registered;
++};
++
++void kmsg_dump(enum kmsg_dump_reason reason);
++
++int kmsg_dump_register(struct kmsg_dumper *dumper);
++
++int kmsg_dump_unregister(struct kmsg_dumper *dumper);
++
++#endif /* _LINUX_KMSG_DUMP_H */
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -10,6 +10,7 @@
+ */
+ #include <linux/debug_locks.h>
+ #include <linux/interrupt.h>
++#include <linux/kmsg_dump.h>
+ #include <linux/kallsyms.h>
+ #include <linux/notifier.h>
+ #include <linux/module.h>
+@@ -74,6 +75,7 @@
+ dump_stack();
+ #endif
+
++ kmsg_dump(KMSG_DUMP_PANIC);
+ /*
+ * If we have crashed and we have a crash kernel loaded let it handle
+ * everything else.
+@@ -337,6 +339,7 @@
+ {
+ do_oops_enter_exit();
+ print_oops_end_marker();
++ kmsg_dump(KMSG_DUMP_OOPS);
+ }
+
+ #ifdef WANT_WARN_ON_SLOWPATH
+--- a/kernel/printk.c
++++ b/kernel/printk.c
+@@ -33,6 +33,7 @@
+ #include <linux/bootmem.h>
+ #include <linux/syscalls.h>
+ #include <linux/kexec.h>
++#include <linux/kmsg_dump.h>
+
+ #include <asm/uaccess.h>
+
+@@ -1322,3 +1323,121 @@
+ }
+ EXPORT_SYMBOL(printk_timed_ratelimit);
+ #endif
++
++static DEFINE_SPINLOCK(dump_list_lock);
++static LIST_HEAD(dump_list);
++
++/**
++ * kmsg_dump_register - register a kernel log dumper.
++ * @dump: pointer to the kmsg_dumper structure
++ *
++ * Adds a kernel log dumper to the system. The dump callback in the
++ * structure will be called when the kernel oopses or panics and must be
++ * set. Returns zero on success and %-EINVAL or %-EBUSY otherwise.
++ */
++int kmsg_dump_register(struct kmsg_dumper *dumper)
++{
++ unsigned long flags;
++ int err = -EBUSY;
++
++ /* The dump callback needs to be set */
++ if (!dumper->dump)
++ return -EINVAL;
++
++ spin_lock_irqsave(&dump_list_lock, flags);
++ /* Don't allow registering multiple times */
++ if (!dumper->registered) {
++ dumper->registered = 1;
++ list_add_tail(&dumper->list, &dump_list);
++ err = 0;
++ }
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++
++ return err;
++}
++EXPORT_SYMBOL_GPL(kmsg_dump_register);
++
++/**
++ * kmsg_dump_unregister - unregister a kmsg dumper.
++ * @dump: pointer to the kmsg_dumper structure
++ *
++ * Removes a dump device from the system. Returns zero on success and
++ * %-EINVAL otherwise.
++ */
++int kmsg_dump_unregister(struct kmsg_dumper *dumper)
++{
++ unsigned long flags;
++ int err = -EINVAL;
++
++ spin_lock_irqsave(&dump_list_lock, flags);
++ if (dumper->registered) {
++ dumper->registered = 0;
++ list_del(&dumper->list);
++ err = 0;
++ }
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++
++ return err;
++}
++EXPORT_SYMBOL_GPL(kmsg_dump_unregister);
++
++static const char const *kmsg_reasons[] = {
++ [KMSG_DUMP_OOPS] = "oops",
++ [KMSG_DUMP_PANIC] = "panic",
++};
++
++static const char *kmsg_to_str(enum kmsg_dump_reason reason)
++{
++ if (reason >= ARRAY_SIZE(kmsg_reasons) || reason < 0)
++ return "unknown";
++
++ return kmsg_reasons[reason];
++}
++
++/**
++ * kmsg_dump - dump kernel log to kernel message dumpers.
++ * @reason: the reason (oops, panic etc) for dumping
++ *
++ * Iterate through each of the dump devices and call the oops/panic
++ * callbacks with the log buffer.
++ */
++void kmsg_dump(enum kmsg_dump_reason reason)
++{
++ unsigned long end;
++ unsigned chars;
++ struct kmsg_dumper *dumper;
++ const char *s1, *s2;
++ unsigned long l1, l2;
++ unsigned long flags;
++
++ /* Theoretically, the log could move on after we do this, but
++ there's not a lot we can do about that. The new messages
++ will overwrite the start of what we dump. */
++ spin_lock_irqsave(&logbuf_lock, flags);
++ end = log_end & LOG_BUF_MASK;
++ chars = logged_chars;
++ spin_unlock_irqrestore(&logbuf_lock, flags);
++
++ if (logged_chars > end) {
++ s1 = log_buf + log_buf_len - logged_chars + end;
++ l1 = logged_chars - end;
++
++ s2 = log_buf;
++ l2 = end;
++ } else {
++ s1 = "";
++ l1 = 0;
++
++ s2 = log_buf + end - logged_chars;
++ l2 = logged_chars;
++ }
++
++ if (!spin_trylock_irqsave(&dump_list_lock, flags)) {
++ printk(KERN_ERR "dump_kmsg: dump list lock is held during %s, skipping dump\n",
++ kmsg_to_str(reason));
++ return;
++ }
++ list_for_each_entry(dumper, &dump_list, list)
++ dumper->dump(dumper, reason, s1, l1, s2, l2);
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++}
--- /dev/null
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -723,6 +723,9 @@
+ Allow user space to create what appear to be multiple instances
+ of the network stack.
+
++config CRASHLOG
++ bool "Crash logging"
++
+ config BLK_DEV_INITRD
+ bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
+ depends on BROKEN || !FRV
+--- a/kernel/Makefile
++++ b/kernel/Makefile
+@@ -95,6 +95,7 @@
+ obj-$(CONFIG_TRACING) += trace/
+ obj-$(CONFIG_SMP) += sched_cpupri.o
+ obj-$(CONFIG_SLOW_WORK) += slow-work.o
++obj-$(CONFIG_CRASHLOG) += crashlog.o
+
+ ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
+ # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
+--- a/mm/bootmem.c
++++ b/mm/bootmem.c
+@@ -12,6 +12,7 @@
+ #include <linux/pfn.h>
+ #include <linux/bootmem.h>
+ #include <linux/module.h>
++#include <linux/crashlog.h>
+
+ #include <asm/bug.h>
+ #include <asm/io.h>
+@@ -151,6 +152,7 @@
+ if (!bdata->node_bootmem_map)
+ return 0;
+
++ crashlog_init_mem(bdata);
+ start = bdata->node_min_pfn;
+ end = bdata->node_low_pfn;
+
+--- a/kernel/module.c
++++ b/kernel/module.c
+@@ -71,6 +71,9 @@
+ DEFINE_MUTEX(module_mutex);
+ EXPORT_SYMBOL_GPL(module_mutex);
+ static LIST_HEAD(modules);
++#ifdef CONFIG_CRASHLOG
++struct list_head *crashlog_modules = &modules;
++#endif
+
+ /* Waiting for a module to finish initializing? */
+ static DECLARE_WAIT_QUEUE_HEAD(module_wq);
+--- /dev/null
++++ b/include/linux/crashlog.h
+@@ -0,0 +1,12 @@
++#ifndef __CRASHLOG_H
++#define __CRASHLOG_H
++
++#ifdef CONFIG_CRASHLOG
++void __init crashlog_init_mem(struct bootmem_data *bdata);
++#else
++static inline void crashlog_init_mem(struct bootmem_data *bdata)
++{
++}
++#endif
++
++#endif
+--- /dev/null
++++ b/kernel/crashlog.c
+@@ -0,0 +1,171 @@
++/*
++ * Crash information logger
++ * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
++ *
++ * 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/debugfs.h>
++#include <linux/crashlog.h>
++#include <linux/kmsg_dump.h>
++#include <linux/module.h>
++#include <linux/pfn.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;
++
++void __init crashlog_init_mem(bootmem_data_t *bdata)
++{
++ unsigned long addr;
++
++ if (crashlog_addr)
++ return;
++
++ addr = PFN_PHYS(bdata->node_low_pfn) - CRASHLOG_OFFSET;
++ if (reserve_bootmem(addr, CRASHLOG_SIZE, BOOTMEM_EXCLUSIVE) < 0) {
++ printk("Crashlog failed to allocate RAM at address 0x%lx\n", addr);
++ bdata->node_low_pfn -= CRASHLOG_PAGES;
++ addr = PFN_PHYS(bdata->node_low_pfn);
++ }
++ crashlog_addr = addr;
++}
++
++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 += vsnprintf(
++ &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, const char *s1, unsigned long l1,
++ const char *s2, unsigned long l2)
++{
++ unsigned long s1_start, s2_start;
++ unsigned long l1_cpy, l2_cpy;
++ struct timeval tv;
++ struct module *m;
++ char *buf;
++ int 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];
++ len = get_maxlen();
++
++ l2_cpy = min(l2, (unsigned long)len);
++ l1_cpy = min(l1, (unsigned long)len - l2_cpy);
++
++ s2_start = l2 - l2_cpy;
++ s1_start = l1 - l1_cpy;
++
++ memcpy(buf, s1 + s1_start, l1_cpy);
++ memcpy(buf + l1_cpy, s2 + s2_start, l2_cpy);
++ crashlog_buf->len += l1_cpy + l2_cpy;
++}
++
++
++int __init crashlog_init_fs(void)
++{
++ if (!crashlog_addr)
++ return -ENOMEM;
++
++ crashlog_buf = ioremap(crashlog_addr, CRASHLOG_SIZE);
++
++ crashlog_copy();
++
++ crashlog_buf->magic = CRASHLOG_MAGIC;
++ crashlog_buf->len = 0;
++
++ dump.dump = crashlog_do_dump;
++ kmsg_dump_register(&dump);
++
++ return 0;
++}
++module_init(crashlog_init_fs);
--- /dev/null
+--- /dev/null
++++ b/include/linux/kmsg_dump.h
+@@ -0,0 +1,44 @@
++/*
++ * linux/include/kmsg_dump.h
++ *
++ * Copyright (C) 2009 Net Insight AB
++ *
++ * Author: Simon Kagstrom <simon.kagstrom@netinsight.net>
++ *
++ * This file is subject to the terms and conditions of the GNU General Public
++ * License. See the file COPYING in the main directory of this archive
++ * for more details.
++ */
++#ifndef _LINUX_KMSG_DUMP_H
++#define _LINUX_KMSG_DUMP_H
++
++#include <linux/list.h>
++
++enum kmsg_dump_reason {
++ KMSG_DUMP_OOPS,
++ KMSG_DUMP_PANIC,
++};
++
++/**
++ * struct kmsg_dumper - kernel crash message dumper structure
++ * @dump: The callback which gets called on crashes. The buffer is passed
++ * as two sections, where s1 (length l1) contains the older
++ * messages and s2 (length l2) contains the newer.
++ * @list: Entry in the dumper list (private)
++ * @registered: Flag that specifies if this is already registered
++ */
++struct kmsg_dumper {
++ void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
++ const char *s1, unsigned long l1,
++ const char *s2, unsigned long l2);
++ struct list_head list;
++ int registered;
++};
++
++void kmsg_dump(enum kmsg_dump_reason reason);
++
++int kmsg_dump_register(struct kmsg_dumper *dumper);
++
++int kmsg_dump_unregister(struct kmsg_dumper *dumper);
++
++#endif /* _LINUX_KMSG_DUMP_H */
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -10,6 +10,7 @@
+ */
+ #include <linux/debug_locks.h>
+ #include <linux/interrupt.h>
++#include <linux/kmsg_dump.h>
+ #include <linux/kallsyms.h>
+ #include <linux/notifier.h>
+ #include <linux/module.h>
+@@ -74,6 +75,7 @@ NORET_TYPE void panic(const char * fmt,
+ dump_stack();
+ #endif
+
++ kmsg_dump(KMSG_DUMP_PANIC);
+ /*
+ * If we have crashed and we have a crash kernel loaded let it handle
+ * everything else.
+@@ -339,6 +341,7 @@ void oops_exit(void)
+ {
+ do_oops_enter_exit();
+ print_oops_end_marker();
++ kmsg_dump(KMSG_DUMP_OOPS);
+ }
+
+ #ifdef WANT_WARN_ON_SLOWPATH
+--- a/kernel/printk.c
++++ b/kernel/printk.c
+@@ -33,6 +33,7 @@
+ #include <linux/bootmem.h>
+ #include <linux/syscalls.h>
+ #include <linux/kexec.h>
++#include <linux/kmsg_dump.h>
+
+ #include <asm/uaccess.h>
+
+@@ -1405,3 +1406,121 @@ bool printk_timed_ratelimit(unsigned lon
+ }
+ EXPORT_SYMBOL(printk_timed_ratelimit);
+ #endif
++
++static DEFINE_SPINLOCK(dump_list_lock);
++static LIST_HEAD(dump_list);
++
++/**
++ * kmsg_dump_register - register a kernel log dumper.
++ * @dump: pointer to the kmsg_dumper structure
++ *
++ * Adds a kernel log dumper to the system. The dump callback in the
++ * structure will be called when the kernel oopses or panics and must be
++ * set. Returns zero on success and %-EINVAL or %-EBUSY otherwise.
++ */
++int kmsg_dump_register(struct kmsg_dumper *dumper)
++{
++ unsigned long flags;
++ int err = -EBUSY;
++
++ /* The dump callback needs to be set */
++ if (!dumper->dump)
++ return -EINVAL;
++
++ spin_lock_irqsave(&dump_list_lock, flags);
++ /* Don't allow registering multiple times */
++ if (!dumper->registered) {
++ dumper->registered = 1;
++ list_add_tail(&dumper->list, &dump_list);
++ err = 0;
++ }
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++
++ return err;
++}
++EXPORT_SYMBOL_GPL(kmsg_dump_register);
++
++/**
++ * kmsg_dump_unregister - unregister a kmsg dumper.
++ * @dump: pointer to the kmsg_dumper structure
++ *
++ * Removes a dump device from the system. Returns zero on success and
++ * %-EINVAL otherwise.
++ */
++int kmsg_dump_unregister(struct kmsg_dumper *dumper)
++{
++ unsigned long flags;
++ int err = -EINVAL;
++
++ spin_lock_irqsave(&dump_list_lock, flags);
++ if (dumper->registered) {
++ dumper->registered = 0;
++ list_del(&dumper->list);
++ err = 0;
++ }
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++
++ return err;
++}
++EXPORT_SYMBOL_GPL(kmsg_dump_unregister);
++
++static const char const *kmsg_reasons[] = {
++ [KMSG_DUMP_OOPS] = "oops",
++ [KMSG_DUMP_PANIC] = "panic",
++};
++
++static const char *kmsg_to_str(enum kmsg_dump_reason reason)
++{
++ if (reason >= ARRAY_SIZE(kmsg_reasons) || reason < 0)
++ return "unknown";
++
++ return kmsg_reasons[reason];
++}
++
++/**
++ * kmsg_dump - dump kernel log to kernel message dumpers.
++ * @reason: the reason (oops, panic etc) for dumping
++ *
++ * Iterate through each of the dump devices and call the oops/panic
++ * callbacks with the log buffer.
++ */
++void kmsg_dump(enum kmsg_dump_reason reason)
++{
++ unsigned long end;
++ unsigned chars;
++ struct kmsg_dumper *dumper;
++ const char *s1, *s2;
++ unsigned long l1, l2;
++ unsigned long flags;
++
++ /* Theoretically, the log could move on after we do this, but
++ there's not a lot we can do about that. The new messages
++ will overwrite the start of what we dump. */
++ spin_lock_irqsave(&logbuf_lock, flags);
++ end = log_end & LOG_BUF_MASK;
++ chars = logged_chars;
++ spin_unlock_irqrestore(&logbuf_lock, flags);
++
++ if (logged_chars > end) {
++ s1 = log_buf + log_buf_len - logged_chars + end;
++ l1 = logged_chars - end;
++
++ s2 = log_buf;
++ l2 = end;
++ } else {
++ s1 = "";
++ l1 = 0;
++
++ s2 = log_buf + end - logged_chars;
++ l2 = logged_chars;
++ }
++
++ if (!spin_trylock_irqsave(&dump_list_lock, flags)) {
++ printk(KERN_ERR "dump_kmsg: dump list lock is held during %s, skipping dump\n",
++ kmsg_to_str(reason));
++ return;
++ }
++ list_for_each_entry(dumper, &dump_list, list)
++ dumper->dump(dumper, reason, s1, l1, s2, l2);
++ spin_unlock_irqrestore(&dump_list_lock, flags);
++}
--- /dev/null
+--- /dev/null
++++ b/include/linux/crashlog.h
+@@ -0,0 +1,12 @@
++#ifndef __CRASHLOG_H
++#define __CRASHLOG_H
++
++#ifdef CONFIG_CRASHLOG
++void __init crashlog_init_mem(struct bootmem_data *bdata);
++#else
++static inline void crashlog_init_mem(struct bootmem_data *bdata)
++{
++}
++#endif
++
++#endif
+--- a/init/Kconfig
++++ b/init/Kconfig
+@@ -710,6 +710,9 @@ config NET_NS
+ Allow user space to create what appear to be multiple instances
+ of the network stack.
+
++config CRASHLOG
++ bool "Crash logging"
++
+ config BLK_DEV_INITRD
+ bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
+ depends on BROKEN || !FRV
+--- a/kernel/Makefile
++++ b/kernel/Makefile
+@@ -96,6 +96,7 @@ obj-$(CONFIG_SMP) += sched_cpupri.o
+ obj-$(CONFIG_SLOW_WORK) += slow-work.o
+ obj-$(CONFIG_SLOW_WORK_DEBUG) += slow-work-debugfs.o
+ obj-$(CONFIG_PERF_EVENTS) += perf_event.o
++obj-$(CONFIG_CRASHLOG) += crashlog.o
+
+ ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
+ # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
+--- /dev/null
++++ b/kernel/crashlog.c
+@@ -0,0 +1,171 @@
++/*
++ * Crash information logger
++ * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
++ *
++ * 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/debugfs.h>
++#include <linux/crashlog.h>
++#include <linux/kmsg_dump.h>
++#include <linux/module.h>
++#include <linux/pfn.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;
++
++void __init crashlog_init_mem(bootmem_data_t *bdata)
++{
++ unsigned long addr;
++
++ if (crashlog_addr)
++ return;
++
++ addr = PFN_PHYS(bdata->node_low_pfn) - CRASHLOG_OFFSET;
++ if (reserve_bootmem(addr, CRASHLOG_SIZE, BOOTMEM_EXCLUSIVE) < 0) {
++ printk("Crashlog failed to allocate RAM at address 0x%lx\n", addr);
++ bdata->node_low_pfn -= CRASHLOG_PAGES;
++ addr = PFN_PHYS(bdata->node_low_pfn);
++ }
++ crashlog_addr = addr;
++}
++
++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 += vsnprintf(
++ &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, const char *s1, unsigned long l1,
++ const char *s2, unsigned long l2)
++{
++ unsigned long s1_start, s2_start;
++ unsigned long l1_cpy, l2_cpy;
++ struct timeval tv;
++ struct module *m;
++ char *buf;
++ int 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];
++ len = get_maxlen();
++
++ l2_cpy = min(l2, (unsigned long)len);
++ l1_cpy = min(l1, (unsigned long)len - l2_cpy);
++
++ s2_start = l2 - l2_cpy;
++ s1_start = l1 - l1_cpy;
++
++ memcpy(buf, s1 + s1_start, l1_cpy);
++ memcpy(buf + l1_cpy, s2 + s2_start, l2_cpy);
++ crashlog_buf->len += l1_cpy + l2_cpy;
++}
++
++
++int __init crashlog_init_fs(void)
++{
++ if (!crashlog_addr)
++ return -ENOMEM;
++
++ crashlog_buf = ioremap(crashlog_addr, CRASHLOG_SIZE);
++
++ crashlog_copy();
++
++ crashlog_buf->magic = CRASHLOG_MAGIC;
++ crashlog_buf->len = 0;
++
++ dump.dump = crashlog_do_dump;
++ kmsg_dump_register(&dump);
++
++ return 0;
++}
++module_init(crashlog_init_fs);
+--- a/mm/bootmem.c
++++ b/mm/bootmem.c
+@@ -13,6 +13,7 @@
+ #include <linux/bootmem.h>
+ #include <linux/module.h>
+ #include <linux/kmemleak.h>
++#include <linux/crashlog.h>
+
+ #include <asm/bug.h>
+ #include <asm/io.h>
+@@ -152,6 +153,7 @@ static unsigned long __init free_all_boo
+ if (!bdata->node_bootmem_map)
+ return 0;
+
++ crashlog_init_mem(bdata);
+ start = bdata->node_min_pfn;
+ end = bdata->node_low_pfn;
+
+--- a/kernel/module.c
++++ b/kernel/module.c
+@@ -79,6 +79,9 @@ EXPORT_TRACEPOINT_SYMBOL(module_get);
+ DEFINE_MUTEX(module_mutex);
+ EXPORT_SYMBOL_GPL(module_mutex);
+ static LIST_HEAD(modules);
++#ifdef CONFIG_CRASHLOG
++struct list_head *crashlog_modules = &modules;
++#endif
+
+ /* Block module loading/unloading? */
+ int modules_disabled = 0;
CONFIG_CON_CHAN="xterm"
CONFIG_CON_ZERO_CHAN="fd:0,fd:1"
CONFIG_CRAMFS=y
+# CONFIG_CRASHLOG is not set
# CONFIG_CRYPTO_AES_586 is not set
# CONFIG_CRYPTO_SALSA20_586 is not set
# CONFIG_CRYPTO_TWOFISH_586 is not set
CONFIG_CON_CHAN="xterm"
CONFIG_CON_ZERO_CHAN="fd:0,fd:1"
CONFIG_CRAMFS=y
+# CONFIG_CRASHLOG is not set
# CONFIG_CRYPTO_AES_NI_INTEL is not set
# CONFIG_CRYPTO_AES_X86_64 is not set
# CONFIG_CRYPTO_SALSA20_X86_64 is not set
projects / openwrt / svn-archive / archive.git / commitdiff