From 9f6c22b4974a89a24c0d8758eb9b9b57a93867a4 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Tue, 20 Jul 2010 01:54:21 +0000 Subject: kernel: add the new 'crashlog' feature, which tries to store kernel oops/panic logs in a fixed location in RAM to recover them after the reboot and make them available to user space using debugfs SVN-Revision: 22305 --- .../generic/patches-2.6.34/930-crashlog.patch | 241 +++++++++++++++++++++ 1 file changed, 241 insertions(+) create mode 100644 target/linux/generic/patches-2.6.34/930-crashlog.patch (limited to 'target/linux/generic/patches-2.6.34') diff --git a/target/linux/generic/patches-2.6.34/930-crashlog.patch b/target/linux/generic/patches-2.6.34/930-crashlog.patch new file mode 100644 index 0000000..ab6f542 --- /dev/null +++ b/target/linux/generic/patches-2.6.34/930-crashlog.patch @@ -0,0 +1,241 @@ +--- /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 +@@ -715,6 +715,9 @@ 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 +@@ -105,6 +105,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_event. + obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o + obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o + obj-$(CONFIG_PADATA) += padata.o ++obj-$(CONFIG_CRASHLOG) += crashlog.o + + ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) + # According to Alan Modra , the -fno-omit-frame-pointer is +--- /dev/null ++++ b/kernel/crashlog.c +@@ -0,0 +1,171 @@ ++/* ++ * Crash information logger ++ * Copyright (C) 2010 Felix Fietkau ++ * ++ * Based on ramoops.c ++ * Copyright (C) 2010 Marco Stornelli ++ * ++ * 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 ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#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 +@@ -15,6 +15,7 @@ + #include + #include + #include ++#include + + #include + #include +@@ -226,6 +227,7 @@ 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; -- cgit v1.1