74 lines
2.4 KiB
Python
74 lines
2.4 KiB
Python
#
|
|
# gdb helper commands and functions for Linux kernel debugging
|
|
#
|
|
# kernel log buffer dump
|
|
#
|
|
# Copyright (c) Siemens AG, 2011, 2012
|
|
#
|
|
# Authors:
|
|
# Jan Kiszka <jan.kiszka@siemens.com>
|
|
#
|
|
# This work is licensed under the terms of the GNU GPL version 2.
|
|
#
|
|
|
|
import gdb
|
|
import sys
|
|
|
|
from linux import utils
|
|
|
|
|
|
class LxDmesg(gdb.Command):
|
|
"""Print Linux kernel log buffer."""
|
|
|
|
def __init__(self):
|
|
super(LxDmesg, self).__init__("lx-dmesg", gdb.COMMAND_DATA)
|
|
|
|
def invoke(self, arg, from_tty):
|
|
log_buf_addr = int(str(gdb.parse_and_eval(
|
|
"(void *)'printk.c'::log_buf")).split()[0], 16)
|
|
log_first_idx = int(gdb.parse_and_eval("'printk.c'::log_first_idx"))
|
|
log_next_idx = int(gdb.parse_and_eval("'printk.c'::log_next_idx"))
|
|
log_buf_len = int(gdb.parse_and_eval("'printk.c'::log_buf_len"))
|
|
|
|
inf = gdb.inferiors()[0]
|
|
start = log_buf_addr + log_first_idx
|
|
if log_first_idx < log_next_idx:
|
|
log_buf_2nd_half = -1
|
|
length = log_next_idx - log_first_idx
|
|
log_buf = utils.read_memoryview(inf, start, length).tobytes()
|
|
else:
|
|
log_buf_2nd_half = log_buf_len - log_first_idx
|
|
a = utils.read_memoryview(inf, start, log_buf_2nd_half)
|
|
b = utils.read_memoryview(inf, log_buf_addr, log_next_idx)
|
|
log_buf = a.tobytes() + b.tobytes()
|
|
|
|
pos = 0
|
|
while pos < log_buf.__len__():
|
|
length = utils.read_u16(log_buf[pos + 8:pos + 10])
|
|
if length == 0:
|
|
if log_buf_2nd_half == -1:
|
|
gdb.write("Corrupted log buffer!\n")
|
|
break
|
|
pos = log_buf_2nd_half
|
|
continue
|
|
|
|
text_len = utils.read_u16(log_buf[pos + 10:pos + 12])
|
|
text = log_buf[pos + 16:pos + 16 + text_len].decode(
|
|
encoding='utf8', errors='replace')
|
|
time_stamp = utils.read_u64(log_buf[pos:pos + 8])
|
|
|
|
for line in text.splitlines():
|
|
msg = u"[{time:12.6f}] {line}\n".format(
|
|
time=time_stamp / 1000000000.0,
|
|
line=line)
|
|
# With python2 gdb.write will attempt to convert unicode to
|
|
# ascii and might fail so pass an utf8-encoded str instead.
|
|
if sys.hexversion < 0x03000000:
|
|
msg = msg.encode(encoding='utf8', errors='replace')
|
|
gdb.write(msg)
|
|
|
|
pos += length
|
|
|
|
|
|
LxDmesg()
|