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-rw-r--r--target/linux/generic/hack-5.4/930-crashlog.patch338
1 files changed, 338 insertions, 0 deletions
diff --git a/target/linux/generic/hack-5.4/930-crashlog.patch b/target/linux/generic/hack-5.4/930-crashlog.patch
new file mode 100644
index 0000000000..bb16f22915
--- /dev/null
+++ b/target/linux/generic/hack-5.4/930-crashlog.patch
@@ -0,0 +1,338 @@
+From 6b1ab74a9917012d0c559edc4ed299d9228ac89f Mon Sep 17 00:00:00 2001
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sat, 8 Jul 2017 08:26:47 +0200
+Subject: kernel: add the new 'crashlog' feature
+
+this tries to store kernel oops/panic logs in a fixed location in RAM to
+recover them available to user space using debugfs
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+ include/linux/crashlog.h | 17 ++++
+ init/Kconfig | 4 +
+ kernel/Makefile | 1 +
+ kernel/crashlog.c | 213 +++++++++++++++++++++++++++++++++++++++++++++++
+ kernel/module.c | 3 +
+ mm/bootmem.c | 2 +
+ mm/memblock.c | 5 ++
+ 7 files changed, 245 insertions(+)
+ create mode 100644 include/linux/crashlog.h
+ create mode 100644 kernel/crashlog.c
+
+--- /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
+@@ -1049,6 +1049,10 @@ 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"
+ help
+--- a/kernel/Makefile
++++ b/kernel/Makefile
+@@ -114,6 +114,7 @@ obj-$(CONFIG_TORTURE_TEST) += torture.o
+ obj-$(CONFIG_HAS_IOMEM) += iomem.o
+ obj-$(CONFIG_ZONE_DEVICE) += memremap.o
+ obj-$(CONFIG_RSEQ) += rseq.o
++obj-$(CONFIG_CRASHLOG) += crashlog.o
+
+ $(obj)/configs.o: $(obj)/config_data.h
+
+--- /dev/null
++++ b/kernel/crashlog.c
+@@ -0,0 +1,213 @@
++/*
++ * 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;
++
++ if (addr + size > CRASHLOG_OFFSET)
++ crashlog_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->core_layout.base, m->core_layout.size,
++ m->init_layout.base, m->init_layout.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
+@@ -251,6 +251,9 @@ 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/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/bug.h>
+ #include <linux/io.h>
+ #include <linux/bootmem.h>
+@@ -215,6 +216,7 @@ 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;
+--- a/mm/memblock.c
++++ b/mm/memblock.c
+@@ -21,6 +21,7 @@
+ #include <linux/seq_file.h>
+ #include <linux/memblock.h>
+ #include <linux/bootmem.h>
++#include <linux/crashlog.h>
+
+ #include <asm/sections.h>
+ #include <linux/io.h>
+@@ -547,6 +548,8 @@ 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);
+ }
+
+ /**
+@@ -586,6 +589,8 @@ 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: