diff options
Diffstat (limited to 'target/linux/generic/hack-5.4/930-crashlog.patch')
| -rw-r--r-- | target/linux/generic/hack-5.4/930-crashlog.patch | 338 |
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: |