[PATCH] crash-trace-command: fix accessing uninitialized data (was: Re: crash utility trace extension module bug)
by Lai Jiangshan
Dave Anderson wrote:
> Hello Lai,
>
> I was assigned a Red Hat bugzilla today, for which I am asking your
> assistance:
>
> https://bugzilla.redhat.com/show_bug.cgi?id=592887
>
Subject: [PATCH] crash-trace-command: fix accessing uninitialized data
Caspar Zhang reported that trace show -c <CPU> causes seg fault.
It's because the path is accessing some uninitialized data and causes seg fault.
Reported-by: Caspar Zhang <czhang(a)redhat.com>
Signed-off-by: Lai Jiangshan <laijs(a)cn.fujitsu.com>
---
diff --git a/extensions/trace.c b/extensions/trace.c
index 975756b..89eb477 100755
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -279,8 +279,12 @@ static void ftrace_destroy_buffers(struct ring_buffer_per_cpu *buffers)
{
int i;
- for (i = 0; i < nr_cpu_ids; i++)
+ for (i = 0; i < nr_cpu_ids; i++) {
+ if (!buffers[i].kaddr)
+ continue;
+
free(buffers[i].pages);
+ }
}
static int ftrace_init_buffers(struct ring_buffer_per_cpu *buffers,
@@ -913,6 +917,7 @@ static int ftrace_dump_event_types(const char *events_path)
}
struct ring_buffer_per_cpu_stream {
+ struct ring_buffer_per_cpu *cpu_buffer;
ulong *pages;
void *curr_page;
int available_pages;
@@ -929,6 +934,7 @@ int ring_buffer_per_cpu_stream_init(struct ring_buffer_per_cpu *cpu_buffer,
{
unsigned i, count = 0;
+ s->cpu_buffer = cpu_buffer;
s->curr_page = malloc(PAGESIZE());
if (s->curr_page == NULL)
return -1;
@@ -1104,9 +1110,7 @@ static void __rbs_destroy(struct ring_buffer_stream *s, int *cpulist, int nr)
int cpu;
for (cpu = 0; cpu < nr; cpu++) {
- if (!global_buffers[cpu].kaddr)
- continue;
- if (cpulist && !cpulist[cpu])
+ if (!s->ss[cpu].cpu_buffer)
continue;
ring_buffer_per_cpu_stream_destroy(s->ss + cpu);
@@ -1132,6 +1136,7 @@ int ring_buffer_stream_init(struct ring_buffer_stream *s, int *cpulist)
}
for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
+ s->ss[cpu].cpu_buffer = NULL;
s->es[cpu].data = NULL;
if (!global_buffers[cpu].kaddr)
@@ -1183,7 +1188,7 @@ static int ring_buffer_stream_pop_event(struct ring_buffer_stream *s,
if (s->popped_cpu == nr_cpu_ids) {
for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
- if (!global_buffers[cpu].kaddr)
+ if (!s->ss[cpu].cpu_buffer)
continue;
ring_buffer_per_cpu_stream_pop_event(s->ss + cpu,
14 years, 10 months
[PATCH] crash-trace-command: generate trace.dat from core-file
by Lai Jiangshan
Subject: [PATCH] crash-trace-command: generate trace.dat from core-file
This patch adds a command "trace dump -t" for crash-trace-command
which is extension of crash(8) for analyzing and dumping ftrace from core-file.
This extension already has "trace show" to show what events had happened
before crash, but it is just 1000 lines of code and it is not so
smart as "trace-cmd report". New command "trace dump -t" generates a trace.dat,
and then, we can use "trace-cmd report" for this trace.dat.
trace-cmd(1) is a ftrace tool written by Steven Rostedt <rostedt(a)goodmis.org>.
It includes two tools for showing ftrace events "trace-cmd report" and "kernelshark".
SEE ALSO: trace-cmd(1), trace-cmd-report(1), trace-cmd.dat(5)
Note, this patch does not just improve crash-trace-command, it improves trace-cmd
also. It makes trace-cmd can handle ftrace even the kernel crashed.
Usage:
1) start crash(8) for a core-file, and execute the following command in crash(8):
2) extend <your-path-to-crash-trace-command, example: /usr/lib/crash/trace.so>
3) trace dump -t
4) q<enter> to quit crash
5) trace-cmd report or kernelshark
Signed-off-by: Lai Jiangshan <laijs(a)cn.fujitsu.com>
---
trace.c | 778 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 693 insertions(+), 85 deletions(-)
diff --git a/extensions/trace.c b/extensions/trace.c
index 89eb477..d100869 100755
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -1,7 +1,7 @@
/*
* trace extension module for crash
*
- * Copyright (C) 2009 FUJITSU LIMITED
+ * Copyright (C) 2009, 2010 FUJITSU LIMITED
* Author: Lai Jiangshan <laijs(a)cn.fujitsu.com>
*
* This program is free software; you can redistribute it and/or modify
@@ -53,6 +53,7 @@ static int koffset(list_head, next);
static int koffset(ftrace_event_call, list);
static int koffset(ftrace_event_call, name);
static int koffset(ftrace_event_call, system);
+static int koffset(ftrace_event_call, print_fmt);
static int koffset(ftrace_event_call, id);
static int koffset(ftrace_event_call, fields);
@@ -74,8 +75,11 @@ struct ring_buffer_per_cpu {
ulong reader_page;
ulong real_head_page;
- ulong *pages;
int head_page_index;
+ ulong *pages;
+
+ ulong *linear_pages;
+ int nr_linear_pages;
ulong overrun;
ulong entries;
@@ -112,6 +116,22 @@ static void ftrace_show_destroy(void);
/* Remove the "const" qualifiers for ptr */
#define free(ptr) free((void *)(ptr))
+static int write_and_check(int fd, void *data, size_t size)
+{
+ size_t tot = 0;
+ size_t w;
+
+ do {
+ w = write(fd, data, size - tot);
+ tot += w;
+
+ if (w <= 0)
+ return -1;
+ } while (tot != size);
+
+ return 0;
+}
+
#ifndef PATH_MAX
#define PATH_MAX 4096
#endif
@@ -153,6 +173,7 @@ static void init_offsets(void)
init_offset(ftrace_event_call, list);
init_offset(ftrace_event_call, name);
init_offset(ftrace_event_call, system);
+ init_offset(ftrace_event_call, print_fmt);
init_offset(ftrace_event_call, id);
init_offset(ftrace_event_call, fields);
@@ -199,6 +220,7 @@ static void print_offsets(void)
print_offset(ftrace_event_call, list);
print_offset(ftrace_event_call, name);
print_offset(ftrace_event_call, system);
+ print_offset(ftrace_event_call, print_fmt);
print_offset(ftrace_event_call, id);
print_offset(ftrace_event_call, fields);
@@ -214,7 +236,7 @@ static void print_offsets(void)
static int ftrace_init_pages(struct ring_buffer_per_cpu *cpu_buffer,
unsigned nr_pages)
{
- unsigned j = 0;
+ unsigned j = 0, count = 0;
ulong head, page;
ulong real_head_page = cpu_buffer->head_page;
@@ -222,6 +244,12 @@ static int ftrace_init_pages(struct ring_buffer_per_cpu *cpu_buffer,
if (cpu_buffer->pages == NULL)
return -1;
+ cpu_buffer->linear_pages = calloc(sizeof(ulong), nr_pages + 1);
+ if (cpu_buffer->linear_pages == NULL) {
+ free(cpu_buffer->pages);
+ return -1;
+ }
+
if (lockless_ring_buffer) {
read_value(head, cpu_buffer->kaddr, ring_buffer_per_cpu, pages);
cpu_buffer->pages[j++] = head - koffset(buffer_page, list);
@@ -253,6 +281,8 @@ static int ftrace_init_pages(struct ring_buffer_per_cpu *cpu_buffer,
goto out_fail;
}
+ /* find head page and head_page_index */
+
cpu_buffer->real_head_page = real_head_page;
cpu_buffer->head_page_index = -1;
@@ -268,10 +298,38 @@ static int ftrace_init_pages(struct ring_buffer_per_cpu *cpu_buffer,
goto out_fail;
}
+ /* Setup linear pages */
+
+ cpu_buffer->linear_pages[count++] = cpu_buffer->reader_page;
+
+ if (cpu_buffer->reader_page == cpu_buffer->commit_page)
+ goto done;
+
+ j = cpu_buffer->head_page_index;
+ for (;;) {
+ cpu_buffer->linear_pages[count++] = cpu_buffer->pages[j];
+
+ if (cpu_buffer->pages[j] == cpu_buffer->commit_page)
+ break;
+
+ j++;
+ if (j == nr_pages)
+ j = 0;
+
+ if (j == cpu_buffer->head_page_index) {
+ /* cpu_buffer->commit_page may be corrupted */
+ break;
+ }
+ }
+
+done:
+ cpu_buffer->nr_linear_pages = count;
+
return 0;
out_fail:
free(cpu_buffer->pages);
+ free(cpu_buffer->linear_pages);
return -1;
}
@@ -284,6 +342,7 @@ static void ftrace_destroy_buffers(struct ring_buffer_per_cpu *buffers)
continue;
free(buffers[i].pages);
+ free(buffers[i].linear_pages);
}
}
@@ -470,7 +529,7 @@ static void ftrace_destroy(void)
free(global_buffers);
}
-static int ftrace_dump_page(FILE *out, ulong page, void *page_tmp)
+static int ftrace_dump_page(int fd, ulong page, void *page_tmp)
{
ulong raw_page;
@@ -480,7 +539,8 @@ static int ftrace_dump_page(FILE *out, ulong page, void *page_tmp)
RETURN_ON_ERROR))
goto out_fail;
- fwrite(page_tmp, 1, PAGESIZE(), out);
+ if (write_and_check(fd, page_tmp, PAGESIZE()))
+ return -1;
return 0;
@@ -489,33 +549,15 @@ out_fail:
}
static
-void ftrace_dump_buffer(FILE *out, struct ring_buffer_per_cpu *cpu_buffer,
+void ftrace_dump_buffer(int fd, struct ring_buffer_per_cpu *cpu_buffer,
unsigned pages, void *page_tmp)
{
- unsigned i;
-
- if (ftrace_dump_page(out, cpu_buffer->reader_page, page_tmp) < 0)
- return;
-
- if (cpu_buffer->reader_page == cpu_buffer->commit_page)
- return;
-
- i = cpu_buffer->head_page_index;
- for (;;) {
- if (ftrace_dump_page(out, cpu_buffer->pages[i], page_tmp) < 0)
- break;
-
- if (cpu_buffer->pages[i] == cpu_buffer->commit_page)
- break;
-
- i++;
- if (i == pages)
- i = 0;
+ int i;
- if (i == cpu_buffer->head_page_index) {
- /* cpu_buffer->commit_page may be corrupted */
+ for (i = 0; i < cpu_buffer->nr_linear_pages; i++) {
+ if (ftrace_dump_page(fd, cpu_buffer->linear_pages[i],
+ page_tmp) < 0)
break;
- }
}
}
@@ -540,7 +582,7 @@ static int ftrace_dump_buffers(const char *per_cpu_path)
int i;
void *page_tmp;
char path[PATH_MAX];
- FILE *out;
+ int fd;
page_tmp = malloc(PAGESIZE());
if (page_tmp == NULL)
@@ -558,12 +600,12 @@ static int ftrace_dump_buffers(const char *per_cpu_path)
snprintf(path, sizeof(path), "%s/cpu%d/trace_pipe_raw",
per_cpu_path, i);
- out = fopen(path, "wb");
- if (out == NULL)
+ fd = open(path, O_WRONLY | O_CREAT, 0644);
+ if (fd < 0)
goto out_fail;
- ftrace_dump_buffer(out, cpu_buffer, global_pages, page_tmp);
- fclose(out);
+ ftrace_dump_buffer(fd, cpu_buffer, global_pages, page_tmp);
+ close(fd);
}
free(page_tmp);
@@ -727,6 +769,7 @@ static void ftrace_destroy_event_types(void)
free(event_types[i]->fields);
free(event_types[i]->system);
free(event_types[i]->name);
+ free(event_types[i]->print_fmt);
free(event_types[i]);
}
@@ -746,8 +789,8 @@ static int ftrace_init_event_types(void)
read_value(event, ftrace_events, list_head, next);
while (event != ftrace_events) {
ulong call;
- ulong name_addr, system_addr;
- char name[128], system[128];
+ ulong name_addr, system_addr, print_fmt_addr;
+ char name[128], system[128], print_fmt[4096];
int id;
call = event - koffset(ftrace_event_call, list);
@@ -756,11 +799,14 @@ static int ftrace_init_event_types(void)
read_value(id, call, ftrace_event_call, id);
read_value(name_addr, call, ftrace_event_call, name);
read_value(system_addr, call, ftrace_event_call, system);
+ read_value(print_fmt_addr, call, ftrace_event_call, print_fmt);
if (!read_string(name_addr, name, 128))
goto out_fail;
if (!read_string(system_addr, system, 128))
goto out_fail;
+ if (!read_string(print_fmt_addr, print_fmt, 4096))
+ goto out_fail;
/* Enlarge event types array when need */
if (nr_event_types >= max_types) {
@@ -782,6 +828,7 @@ static int ftrace_init_event_types(void)
aevent_type->system = strdup(system);
aevent_type->name = strdup(name);
+ aevent_type->print_fmt = strdup(print_fmt);
aevent_type->id = id;
aevent_type->nfields = 0;
aevent_type->fields = NULL;
@@ -812,6 +859,7 @@ static int ftrace_init_event_types(void)
out_fail_free_aevent_type:
free(aevent_type->system);
free(aevent_type->name);
+ free(aevent_type->print_fmt);
free(aevent_type);
out_fail:
ftrace_destroy_event_types();
@@ -868,6 +916,7 @@ static int ftrace_dump_event_type(struct event_type *t, const char *path)
char format_path[PATH_MAX];
FILE *out;
int i;
+ int common_field_count = 5;
snprintf(format_path, sizeof(format_path), "%s/format", path);
out = fopen(format_path, "w");
@@ -878,15 +927,40 @@ static int ftrace_dump_event_type(struct event_type *t, const char *path)
fprintf(out, "ID: %d\n", t->id);
fprintf(out, "format:\n");
- for (i = 0; i < t->nfields; i++) {
- struct ftrace_field *f = &t->fields[i];
+ for (i = t->nfields - 1; i >= 0; i--) {
+ /*
+ * Smartly shows the array type(except dynamic array).
+ * Normal:
+ * field:TYPE VAR
+ * If TYPE := TYPE[LEN], it is shown:
+ * field:TYPE VAR[LEN]
+ */
+ struct ftrace_field *field = &t->fields[i];
+ const char *array_descriptor = strchr(field->type, '[');
+
+ if (!strncmp(field->type, "__data_loc", 10))
+ array_descriptor = NULL;
+
+ if (!array_descriptor) {
+ fprintf(out, "\tfield:%s %s;\toffset:%u;"
+ "\tsize:%u;\tsigned:%d;\n",
+ field->type, field->name, field->offset,
+ field->size, !!field->is_signed);
+ } else {
+ fprintf(out, "\tfield:%.*s %s%s;\toffset:%u;"
+ "\tsize:%u;\tsigned:%d;\n",
+ (int)(array_descriptor - field->type),
+ field->type, field->name,
+ array_descriptor, field->offset,
+ field->size, !!field->is_signed);
+ }
- fprintf(out, "\tfield:%s %s;\toffset:%d;\tsize:%d;\n",
- f->type, f->name, f->offset, f->size);
+ if (--common_field_count == 0)
+ fprintf(out, "\n");
}
- /* TODO */
- fprintf(out, "\nprint fmt: \"unknow fmt from dump\"\n");
+ fprintf(out, "\nprint fmt: %s\n", t->print_fmt);
+
fclose(out);
return 0;
@@ -918,9 +992,7 @@ static int ftrace_dump_event_types(const char *events_path)
struct ring_buffer_per_cpu_stream {
struct ring_buffer_per_cpu *cpu_buffer;
- ulong *pages;
void *curr_page;
- int available_pages;
int curr_page_indx;
uint64_t ts;
@@ -932,43 +1004,11 @@ static
int ring_buffer_per_cpu_stream_init(struct ring_buffer_per_cpu *cpu_buffer,
unsigned pages, struct ring_buffer_per_cpu_stream *s)
{
- unsigned i, count = 0;
-
s->cpu_buffer = cpu_buffer;
s->curr_page = malloc(PAGESIZE());
if (s->curr_page == NULL)
return -1;
- s->pages = malloc(sizeof(ulong) * (pages + 1));
- if (s->pages == NULL) {
- free(s->curr_page);
- return -1;
- }
-
- s->pages[count++] = cpu_buffer->reader_page;
-
- if (cpu_buffer->reader_page == cpu_buffer->commit_page)
- goto pages_done;
-
- i = cpu_buffer->head_page_index;
- for (;;) {
- s->pages[count++] = cpu_buffer->pages[i];
-
- if (cpu_buffer->pages[i] == cpu_buffer->commit_page)
- break;
-
- i++;
- if (i == pages)
- i = 0;
-
- if (i == cpu_buffer->head_page_index) {
- /* cpu_buffer->commit_page may be corrupted */
- break;
- }
- }
-
-pages_done:
- s->available_pages = count;
s->curr_page_indx = -1;
return 0;
}
@@ -977,7 +1017,6 @@ static
void ring_buffer_per_cpu_stream_destroy(struct ring_buffer_per_cpu_stream *s)
{
free(s->curr_page);
- free(s->pages);
}
struct ftrace_event {
@@ -1003,7 +1042,8 @@ int ring_buffer_per_cpu_stream_get_page(struct ring_buffer_per_cpu_stream *s)
{
ulong raw_page;
- read_value(raw_page, s->pages[s->curr_page_indx], buffer_page, page);
+ read_value(raw_page, s->cpu_buffer->linear_pages[s->curr_page_indx],
+ buffer_page, page);
if (!readmem(raw_page, KVADDR, s->curr_page, PAGESIZE(),
"get page context", RETURN_ON_ERROR))
@@ -1027,18 +1067,18 @@ int ring_buffer_per_cpu_stream_pop_event(struct ring_buffer_per_cpu_stream *s,
res->data = NULL;
- if (s->curr_page_indx >= s->available_pages)
+ if (s->curr_page_indx >= s->cpu_buffer->nr_linear_pages)
return -1;
again:
if ((s->curr_page_indx == -1) || (s->offset >= s->commit)) {
s->curr_page_indx++;
- if (s->curr_page_indx == s->available_pages)
+ if (s->curr_page_indx == s->cpu_buffer->nr_linear_pages)
return -1;
if (ring_buffer_per_cpu_stream_get_page(s) < 0) {
- s->curr_page_indx = s->available_pages;
+ s->curr_page_indx = s->cpu_buffer->nr_linear_pages;
return -1;
}
@@ -1350,6 +1390,39 @@ static int dump_saved_cmdlines(const char *dump_tracing_dir)
return 0;
}
+static int dump_kallsyms(const char *dump_tracing_dir)
+{
+ char path[PATH_MAX];
+ FILE *out;
+ int i;
+ struct syment *sp;
+
+ snprintf(path, sizeof(path), "%s/kallsyms", dump_tracing_dir);
+ out = fopen(path, "w");
+ if (out == NULL)
+ return -1;
+
+ for (sp = st->symtable; sp < st->symend; sp++)
+ fprintf(out, "%lx %c %s\n", sp->value, sp->type, sp->name);
+
+ for (i = 0; i < st->mods_installed; i++) {
+ struct load_module *lm = &st->load_modules[i];
+
+ for (sp = lm->mod_symtable; sp <= lm->mod_symend; sp++) {
+ if (!strncmp(sp->name, "_MODULE_", strlen("_MODULE_")))
+ continue;
+
+ fprintf(out, "%lx %c %s\t[%s]\n", sp->value, sp->type,
+ sp->name, lm->mod_name);
+ }
+ }
+
+ fclose(out);
+ return 0;
+}
+
+static int trace_cmd_data_output(int fd);
+
static void ftrace_dump(int argc, char *argv[])
{
int c;
@@ -1359,7 +1432,7 @@ static void ftrace_dump(int argc, char *argv[])
char path[PATH_MAX];
int ret;
- while ((c = getopt(argc, argv, "sm")) != EOF) {
+ while ((c = getopt(argc, argv, "smt")) != EOF) {
switch(c)
{
case 's':
@@ -1368,6 +1441,23 @@ static void ftrace_dump(int argc, char *argv[])
case 'm':
dump_meta_data = 1;
break;
+ case 't':
+ if (dump_symbols || dump_meta_data || argc - optind > 1)
+ cmd_usage(pc->curcmd, SYNOPSIS);
+ else {
+ char *trace_dat;
+ int fd;
+
+ if (argc - optind == 0)
+ trace_dat = "trace.dat";
+ else if (argc - optind == 1)
+ trace_dat = argv[optind];
+ fd = open(trace_dat, O_WRONLY | O_CREAT
+ | O_TRUNC, 0644);
+ trace_cmd_data_output(fd);
+ close(fd);
+ }
+ return;
default:
cmd_usage(pc->curcmd, SYNOPSIS);
return;
@@ -1413,10 +1503,7 @@ static void ftrace_dump(int argc, char *argv[])
if (dump_symbols) {
/* Dump all symbols of the kernel */
- fprintf(fp, "\n-s option hasn't been implemented.\n");
- fprintf(fp, "symbols is not dumpped.\n");
- fprintf(fp, "You can use `sym -l > %s/kallsyms`\n\n",
- dump_tracing_dir);
+ dump_kallsyms(dump_tracing_dir);
}
}
@@ -2508,6 +2595,9 @@ static char *help_ftrace[] = {
" the same as debugfs/tracing.",
" -m: also dump metadata of ftrace.",
" -s: also dump symbols of the kernel <not implemented>.",
+"trace dump -t [output-file-name]",
+" dump ring_buffers and all meta data to a file that can",
+" be parsed by trace-cmd. Default output file name is \"trace.dat\".",
NULL
};
@@ -2536,3 +2626,521 @@ int _fini(void)
return 1;
}
+
+#define TRACE_CMD_FILE_VERSION_STRING "6"
+
+static inline int host_bigendian(void)
+{
+ unsigned char str[] = { 0x1, 0x2, 0x3, 0x4 };
+ unsigned int *ptr;
+
+ ptr = (unsigned int *)str;
+ return *ptr == 0x01020304;
+}
+
+static char *tmp_file_buf;
+static unsigned long long tmp_file_pos;
+static unsigned long long tmp_file_size;
+static int tmp_file_error;
+
+static int init_tmp_file(void)
+{
+ tmp_file_buf = malloc(4096);
+ if (tmp_file_buf == NULL)
+ return -1;
+
+ tmp_file_pos = 0;
+ tmp_file_size = 4096;
+ tmp_file_error = 0;
+
+ return 0;
+}
+
+static void destory_tmp_file(void)
+{
+ free(tmp_file_buf);
+}
+
+#define tmp_fprintf(fmt...) \
+do { \
+ char *__buf = tmp_file_buf; \
+ unsigned long long __pos; \
+ \
+ if (tmp_file_error) \
+ break; \
+ __pos = tmp_file_pos; \
+ __pos += snprintf(__buf + __pos, tmp_file_size - __pos, fmt); \
+ if (__pos > tmp_file_size) { \
+ tmp_file_size = __pos + tmp_file_size; \
+ __buf = realloc(__buf, tmp_file_size); \
+ if (!__buf) { \
+ tmp_file_error = 1; \
+ break; \
+ } \
+ tmp_file_buf = __buf; \
+ __pos = tmp_file_pos; \
+ __pos += snprintf(__buf + __pos, tmp_file_size - __pos, fmt);\
+ } \
+ tmp_file_pos = __pos; \
+} while (0)
+
+static int tmp_file_record_size4(int fd)
+{
+ unsigned int size = tmp_file_pos;
+
+ if (tmp_file_error)
+ return -1;
+ if (write_and_check(fd, &size, 4))
+ return -1;
+ return 0;
+}
+
+static int tmp_file_record_size8(int fd)
+{
+ if (tmp_file_error)
+ return -1;
+ if (write_and_check(fd, &tmp_file_pos, 8))
+ return -1;
+ return 0;
+}
+
+static int tmp_file_flush(int fd)
+{
+ if (tmp_file_error)
+ return -1;
+ if (write_and_check(fd, tmp_file_buf, tmp_file_pos))
+ return -1;
+ tmp_file_pos = 0;
+ return 0;
+}
+
+static int save_initial_data(int fd)
+{
+ int page_size;
+ char buf[20];
+
+ if (write_and_check(fd, "\027\010\104tracing", 10))
+ return -1;
+
+ if (write_and_check(fd, TRACE_CMD_FILE_VERSION_STRING,
+ strlen(TRACE_CMD_FILE_VERSION_STRING) + 1))
+ return -1;
+
+ /* Crash ensure core file endian and the host endian are the same */
+ if (host_bigendian())
+ buf[0] = 1;
+ else
+ buf[0] = 0;
+
+ if (write_and_check(fd, buf, 1))
+ return -1;
+
+ /* save size of long (this may not be what the kernel is) */
+ buf[0] = sizeof(long);
+ if (write_and_check(fd, buf, 1))
+ return -1;
+
+ page_size = PAGESIZE();
+ if (write_and_check(fd, &page_size, 4))
+ return -1;
+
+ return 0;
+}
+
+static int save_header_files(int fd)
+{
+ /* save header_page */
+ if (write_and_check(fd, "header_page", 12))
+ return -1;
+
+ tmp_fprintf("\tfield: u64 timestamp;\toffset:0;\tsize:8;\tsigned:0;\n");
+
+ tmp_fprintf("\tfield: local_t commit;\toffset:8;\tsize:%u;\t"
+ "signed:1;\n", (unsigned int)sizeof(long));
+
+ tmp_fprintf("\tfield: int overwrite;\toffset:8;\tsize:%u;\tsigned:1;\n",
+ (unsigned int)sizeof(long));
+
+ tmp_fprintf("\tfield: char data;\toffset:%u;\tsize:%u;\tsigned:1;\n",
+ (unsigned int)(8 + sizeof(long)),
+ (unsigned int)(PAGESIZE() - 8 - sizeof(long)));
+
+ if (tmp_file_record_size8(fd))
+ return -1;
+ if (tmp_file_flush(fd))
+ return -1;
+
+ /* save header_event */
+ if (write_and_check(fd, "header_event", 13))
+ return -1;
+
+ tmp_fprintf(
+ "# compressed entry header\n"
+ "\ttype_len : 5 bits\n"
+ "\ttime_delta : 27 bits\n"
+ "\tarray : 32 bits\n"
+ "\n"
+ "\tpadding : type == 29\n"
+ "\ttime_extend : type == 30\n"
+ "\tdata max type_len == 28\n"
+ );
+
+ if (tmp_file_record_size8(fd))
+ return -1;
+ if (tmp_file_flush(fd))
+ return -1;
+
+ return 0;
+}
+
+static int save_event_file(int fd, struct event_type *t)
+{
+ int i;
+ int common_field_count = 5;
+
+ tmp_fprintf("name: %s\n", t->name);
+ tmp_fprintf("ID: %d\n", t->id);
+ tmp_fprintf("format:\n");
+
+ for (i = t->nfields - 1; i >= 0; i--) {
+ /*
+ * Smartly shows the array type(except dynamic array).
+ * Normal:
+ * field:TYPE VAR
+ * If TYPE := TYPE[LEN], it is shown:
+ * field:TYPE VAR[LEN]
+ */
+ struct ftrace_field *field = &t->fields[i];
+ const char *array_descriptor = strchr(field->type, '[');
+
+ if (!strncmp(field->type, "__data_loc", 10))
+ array_descriptor = NULL;
+
+ if (!array_descriptor) {
+ tmp_fprintf("\tfield:%s %s;\toffset:%u;"
+ "\tsize:%u;\tsigned:%d;\n",
+ field->type, field->name, field->offset,
+ field->size, !!field->is_signed);
+ } else {
+ tmp_fprintf("\tfield:%.*s %s%s;\toffset:%u;"
+ "\tsize:%u;\tsigned:%d;\n",
+ (int)(array_descriptor - field->type),
+ field->type, field->name,
+ array_descriptor, field->offset,
+ field->size, !!field->is_signed);
+ }
+
+ if (--common_field_count == 0)
+ tmp_fprintf("\n");
+ }
+
+ tmp_fprintf("\nprint fmt: %s\n", t->print_fmt);
+
+ if (tmp_file_record_size8(fd))
+ return -1;
+ return tmp_file_flush(fd);
+}
+
+static int save_system_files(int fd, int *system_ids, int system_id)
+{
+ int i, total = 0;
+
+ for (i = 0; i < nr_event_types; i++) {
+ if (system_ids[i] == system_id)
+ total++;
+ }
+
+ if (write_and_check(fd, &total, 4))
+ return -1;
+
+ for (i = 0; i < nr_event_types; i++) {
+ if (system_ids[i] != system_id)
+ continue;
+
+ if (save_event_file(fd, event_types[i]))
+ return -1;
+ }
+
+ return 0;
+}
+
+static int save_events_files(int fd)
+{
+ int system_id = 1, *system_ids;
+ const char *system = "ftrace";
+ int i;
+ int nr_systems;
+
+ system_ids = calloc(sizeof(*system_ids), nr_event_types);
+ if (system_ids == NULL)
+ return -1;
+
+ for (;;) {
+ for (i = 0; i < nr_event_types; i++) {
+ if (system_ids[i])
+ continue;
+ if (!system) {
+ system = event_types[i]->system;
+ system_ids[i] = system_id;
+ continue;
+ }
+ if (!strcmp(event_types[i]->system, system))
+ system_ids[i] = system_id;
+ }
+ if (!system)
+ break;
+ system_id++;
+ system = NULL;
+ }
+
+ /* ftrace events */
+ if (save_system_files(fd, system_ids, 1))
+ goto fail;
+
+ /* other systems events */
+ nr_systems = system_id - 2;
+ if (write_and_check(fd, &nr_systems, 4))
+ goto fail;
+ for (system_id = 2; system_id < nr_systems + 2; system_id++) {
+ for (i = 0; i < nr_event_types; i++) {
+ if (system_ids[i] == system_id)
+ break;
+ }
+ if (write_and_check(fd, (void *)event_types[i]->system,
+ strlen(event_types[i]->system) + 1))
+ goto fail;
+ if (save_system_files(fd, system_ids, system_id))
+ goto fail;
+ }
+
+ free(system_ids);
+ return 0;
+
+fail:
+ free(system_ids);
+ return -1;
+}
+
+static int save_proc_kallsyms(int fd)
+{
+ int i;
+ struct syment *sp;
+
+ for (sp = st->symtable; sp < st->symend; sp++)
+ tmp_fprintf("%lx %c %s\n", sp->value, sp->type, sp->name);
+
+ for (i = 0; i < st->mods_installed; i++) {
+ struct load_module *lm = &st->load_modules[i];
+
+ for (sp = lm->mod_symtable; sp <= lm->mod_symend; sp++) {
+ if (!strncmp(sp->name, "_MODULE_", strlen("_MODULE_")))
+ continue;
+
+ tmp_fprintf("%lx %c %s\t[%s]\n", sp->value, sp->type,
+ sp->name, lm->mod_name);
+ }
+ }
+
+ if (tmp_file_record_size4(fd))
+ return -1;
+ return tmp_file_flush(fd);
+}
+
+static int save_ftrace_printk(int fd)
+{
+ struct syment *s, *e;
+ long bprintk_fmt_s, bprintk_fmt_e;
+ char string[4096];
+ long *address;
+ size_t i, count;
+
+ s = symbol_search("__start___trace_bprintk_fmt");
+ e = symbol_search("__stop___trace_bprintk_fmt");
+ if (s == NULL || e == NULL)
+ return -1;
+
+ bprintk_fmt_s = s->value;
+ bprintk_fmt_e = e->value;
+ count = (bprintk_fmt_e - bprintk_fmt_s) / sizeof(long);
+
+ if (count == 0) {
+ unsigned int size = 0;
+ return write_and_check(fd, &size, 4);
+ }
+
+ address = malloc(count * sizeof(long));
+ if (address == NULL)
+ return -1;
+
+ if (!readmem(bprintk_fmt_s, KVADDR, address, count * sizeof(long),
+ "get printk address", RETURN_ON_ERROR)) {
+ free(address);
+ return -1;
+ }
+
+ for (i = 0; i < count; i++) {
+ size_t len = read_string(address[i], string, sizeof(string));
+ if (!len) {
+ free(address);
+ return -1;
+ }
+
+ tmp_fprintf("0x%lx : \"", address[i]);
+
+ for (i = 0; string[i]; i++) {
+ switch (string[i]) {
+ case '\n':
+ tmp_fprintf("\\n");
+ break;
+ case '\t':
+ tmp_fprintf("\\t");
+ break;
+ case '\\':
+ tmp_fprintf("\\\\");
+ break;
+ case '"':
+ tmp_fprintf("\\\"");
+ break;
+ default:
+ tmp_fprintf("%c", string[i]);
+ }
+ }
+ tmp_fprintf("\"\n");
+ }
+
+ free(address);
+
+ if (tmp_file_record_size4(fd))
+ return -1;
+ return tmp_file_flush(fd);
+}
+
+static int save_ftrace_cmdlines(int fd)
+{
+ int i;
+ struct task_context *tc = FIRST_CONTEXT();
+
+ for (i = 0; i < RUNNING_TASKS(); i++)
+ tmp_fprintf("%d %s\n", (int)tc[i].pid, tc[i].comm);
+
+ if (tmp_file_record_size8(fd))
+ return -1;
+ return tmp_file_flush(fd);
+}
+
+static int save_res_data(int fd, int nr_cpu_buffers)
+{
+ unsigned short option = 0;
+
+ if (write_and_check(fd, &nr_cpu_buffers, 4))
+ return -1;
+
+ if (write_and_check(fd, "options ", 10))
+ return -1;
+
+ if (write_and_check(fd, &option, 2))
+ return -1;
+
+ if (write_and_check(fd, "flyrecord", 10))
+ return -1;
+
+ return 0;
+}
+
+static int save_record_data(int fd, int nr_cpu_buffers)
+{
+ int i, j;
+ unsigned long long offset, buffer_offset;
+ void *page_tmp;
+
+ offset = lseek(fd, 0, SEEK_CUR);
+ offset += nr_cpu_buffers * 16;
+ offset = (offset + (PAGESIZE() - 1)) & ~(PAGESIZE() - 1);
+ buffer_offset = offset;
+
+ for (i = 0; i < nr_cpu_ids; i++) {
+ struct ring_buffer_per_cpu *cpu_buffer = &global_buffers[i];
+ unsigned long long buffer_size;
+
+ if (!cpu_buffer->kaddr)
+ continue;
+
+ buffer_size = PAGESIZE() * cpu_buffer->nr_linear_pages;
+ if (write_and_check(fd, &buffer_offset, 8))
+ return -1;
+ if (write_and_check(fd, &buffer_size, 8))
+ return -1;
+ buffer_offset += buffer_size;
+ }
+
+ page_tmp = malloc(PAGESIZE());
+ if (page_tmp == NULL)
+ return -1;
+
+ lseek(fd, offset, SEEK_SET);
+ for (i = 0; i < nr_cpu_ids; i++) {
+ struct ring_buffer_per_cpu *cpu_buffer = &global_buffers[i];
+
+ if (!cpu_buffer->kaddr)
+ continue;
+
+ for (j = 0; j < cpu_buffer->nr_linear_pages; j++) {
+ if (ftrace_dump_page(fd, cpu_buffer->linear_pages[i],
+ page_tmp) < 0) {
+ free(page_tmp);
+ return -1;
+ }
+ }
+ }
+
+ free(page_tmp);
+
+ return 0;
+}
+
+static int __trace_cmd_data_output(int fd)
+{
+ int i;
+ int nr_cpu_buffers = 0;
+
+ for (i = 0; i < nr_cpu_ids; i++) {
+ struct ring_buffer_per_cpu *cpu_buffer = &global_buffers[i];
+
+ if (!cpu_buffer->kaddr)
+ continue;
+
+ nr_cpu_buffers++;
+ }
+
+ if (save_initial_data(fd))
+ return -1;
+ if (save_header_files(fd))
+ return -1;
+ if (save_events_files(fd)) /* ftrace events and other systems events */
+ return -1;
+ if (save_proc_kallsyms(fd))
+ return -1;
+ if (save_ftrace_printk(fd))
+ return -1;
+ if (save_ftrace_cmdlines(fd))
+ return -1;
+ if (save_res_data(fd, nr_cpu_buffers))
+ return -1;
+ if (save_record_data(fd, nr_cpu_buffers))
+ return -1;
+
+ return 0;
+}
+
+static int trace_cmd_data_output(int fd)
+{
+ int ret;
+
+ if (init_tmp_file())
+ return -1;
+
+ ret = __trace_cmd_data_output(fd);
+ destory_tmp_file();
+
+ return ret;
+}
14 years, 10 months
Re: [Crash-utility] Additional fix for per-cpu data symbol naming problem
by Dave Anderson
----- "Ryota Ozaki" <ozaki.ryota(a)gmail.com> wrote:
> Hi,
>
> I tried crash 5.0.3 for linux 2.6.34 (x86_64) and faced the problem
> about per-cpu data symbol naming, which is described in ChangeLog
> as it's already fixed. I observed to fix the problem and found the
> following fix for x86_64_verify_symbol() in x86_64.c helped me.
>
> I'm not sure whether the fix is correct or not, but it would be help for
> correct fix.
>
> Thanks,
> ozaki-r
>
>
> --- x86_64.c.orig 2010-05-19 12:26:11.000000000 +0000
> +++ x86_64.c 2010-05-19 08:23:30.000000000 +0000
> @@ -1974,7 +1974,7 @@
> if (STRNEQ(name, "per_cpu") ||
> STREQ(name, "__per_cpu_end"))
> return TRUE;
> - if (type == 'V')
> + if (type == 'V' || type == 'D' || type == 'd')
> return TRUE;
> }
Yes, I already have that same patch queued for the next release,
which I hope to have ready today or tomorrow.
The fix in 5.0.3 was based upon my own builds of 2.6.34 kernels
that introduced the new per-cpu symbol naming scheme. But when
I build x86_64 kernels, the per-cpu symbol types are type 'V'.
For example, here's a 2.6.34-rc5 kernel that I built -- note there
are few absolute ('a' or 'A') symbols after "__per_cpu_start", but
all the "real" per-cpu symbols are type 'V':
# strings vmlinux | grep "Linux version"
Linux version 2.6.34-rc5 (root(a)intel-d3c4702-01.rhts.eng.bos.redhat.com) (gcc version 4.4.3 20100121 (Red Hat 4.4.3-1) (GCC) ) #1 SMP Fri Apr 30 18:20:16 EDT 2010
# nm -Bn vmlinux
w __crc_softirq_work_list
U do_hypervisor_callback
0000000000000000 a L3_PAGE_OFFSET
0000000000000000 A VDSO32_PRELINK
0000000000000000 D __per_cpu_start
0000000000000000 V irq_stack_union
0000000000000000 A xen_irq_disable_direct_reloc
0000000000000000 A xen_save_fl_direct_reloc
0000000000000040 A VDSO32_vsyscall_eh_frame_size
0000000000000100 a i
0000000000000100 a vector
0000000000000110 a L4_PAGE_OFFSET
00000000000001e7 A kexec_control_code_size
00000000000001f0 A VDSO32_NOTE_MASK
00000000000001fe a L3_START_KERNEL
00000000000001ff a L4_START_KERNEL
0000000000000400 A VDSO32_sigreturn
0000000000000410 A VDSO32_rt_sigreturn
0000000000000420 A VDSO32_vsyscall
0000000000000430 A VDSO32_SYSENTER_RETURN
0000000000004000 V gdt_page
0000000000005000 V exception_stacks
000000000000b000 V xen_vcpu
000000000000b020 V xen_vcpu_info
000000000000b060 V idt_desc
000000000000b070 V xen_cr0_value
000000000000b080 V xen_mc_irq_flags
000000000000b0a0 V mc_buffer
000000000000c5b0 V xen_cr3
000000000000c5b8 V xen_current_cr3
... [ cut ] ...
0000000000016700 V cpu_tlbstate
0000000000016740 V runqueues
0000000000017100 V sched_clock_data
0000000000017140 V cfd_data
0000000000017180 V call_single_queue
00000000000171c0 V csd_data
00000000000171e8 D __per_cpu_end
...
Although I still don't understand why it happens (compiler?
CONFIG option?), a patch to continue recognizing 'd' and 'D'
symbols is obviously needed.
Thanks,
Dave
14 years, 10 months
Re: [Crash-utility] Why are there two ways of getting register values for active tasks?
by Dave Anderson
----- "Daisuke HATAYAMA" <d.hatayama(a)jp.fujitsu.com> wrote:
> Hi, all.
>
> I have a question on the implementation of get_netdump_regs_x86_64().
>
> Currently, in order to get register values for active tasks, only
> panic task makes use of note information. On the other hand, other
> active tasks search stack frame for registers saved at nmi
> switch. However, crash dump contains the note information for every
> CPUs, so I think it uncessary to search stack frame.
Originally it was done that way because the code was written for
netdump-generated dumpfiles, which only generated note information
for the panic task. But if I'm not mistaken, given that recent
kernels do not store debuginfo data for the user_regs_struct, it
almost always falls through into x86_64_get_stack_frame().
Dave
14 years, 10 months
Additional fix for per-cpu data symbol naming problem
by Ryota Ozaki
Hi,
I tried crash 5.0.3 for linux 2.6.34 (x86_64) and faced the problem
about per-cpu data symbol naming, which is described in ChangeLog
as it's already fixed. I observed to fix the problem and found the
following fix for x86_64_verify_symbol() in x86_64.c helped me.
I'm not sure whether the fix is correct or not, but it would be help for
correct fix.
Thanks,
ozaki-r
--- x86_64.c.orig 2010-05-19 12:26:11.000000000 +0000
+++ x86_64.c 2010-05-19 08:23:30.000000000 +0000
@@ -1974,7 +1974,7 @@
if (STRNEQ(name, "per_cpu") ||
STREQ(name, "__per_cpu_end"))
return TRUE;
- if (type == 'V')
+ if (type == 'V' || type == 'D' || type == 'd')
return TRUE;
}
14 years, 10 months
Why are there two ways of getting register values for active tasks?
by Daisuke HATAYAMA
Hi, all.
I have a question on the implementation of get_netdump_regs_x86_64().
Currently, in order to get register values for active tasks, only
panic task makes use of note information. On the other hand, other
active tasks search stack frame for registers saved at nmi
switch. However, crash dump contains the note information for every
CPUs, so I think it uncessary to search stack frame.
Could anyone tell me why here is implemented this way?
Thanks.
HATAYAMA, Daisuke
14 years, 10 months
Re: [Crash-utility] dev -p command fails post linux 2.6.25
by Dave Anderson
----- "Sharyathi Nagesh" <sharyath(a)in.ibm.com> wrote:
> Dave
> >
> > Actually, at a minimum, I should change this:
> >
> > if (!symbol_exists("pci_devices")) error(FATAL, "no PCI devices found
> > on this system.\n");
> >
> > to the generic option_not_supported() message.
>
> Can you accept this change I basically replaced above error message to
> option_not_supported() call.
> Do let me know your observation
> Thanks
> Sharyathi N
Hi Sharyathi,
The patch that I already have queued is attached:
- Fix the error message for the "dev -p" comand when run on 2.6.26
or later kernels, which no longer have the global "pci_devices"
list head. The patch changes the message to show "dev: -p option
not supported or applicable on this architecture or kernel", instead
of the misleading "dev: no PCI devices found on this system" message.
(anderson(a)redhat.com)
Thanks,
Dave
14 years, 11 months
Re: [Crash-utility] dev -p command fails post linux 2.6.25
by Dave Anderson
----- "Sharyathi Nagesh" <sharyath(a)in.ibm.com> wrote:
> Hi Dave
> As you may be aware dev -p command post linux kernel 2.6.25 fails with
> "no PCI devices found on this system.". When I went through the kernel
> a specific commit has removed pci_devices variable from the kernel code
>
> ==================================================================
> git commit: 5ff580c10ec06fd296bd23d4570c1a95194094a0
> by Greg Kroah-Hartman <gregkh(a)suse.de>
>
>
> This is what he says in the commit
> ------------------------------------------------------------------------------------------------------------
> This patch finally removes the global list of PCI devices. We are
> relying entirely on the list held in the driver core now, and do not
> need a separate "shadow" list as no one uses it.
> ------------------------------------------------------------------------------------------------------------
>
> ==================================================================
>
> I saw some of your earlier postings where you have specifically mentioned about this problem:
> http://www.mail-archive.com/crash-utility@redhat.com/msg00346.html
>
>
> With this I wanted to know, if you intend to keep dev -p behavior as it is now or
> there is any plan to change it to display actual values?
>
> Thank You
> Sharyathi N
I (personally) have no plans to change it. If I remember correctly,
Bud Brown came up with an alternate scheme, but the imported data from
the kernel proper required to accomplish it was enormous (bordering
on absurd), so I suggested that it would be more appropriate as an
extension module.
Bud -- feel free to chime in here... ;-)
For that matter, even the "old" way required the import of ~1000 lines
of kernel #define's -- which always bugged me -- and was pretty much the
only crash command that had to do such a thing.
Dave
14 years, 11 months
