Linux kernel source Documentation / sysctl / kernel.txt core_pattern:
core_pattern: core_pattern is used to specify a core dumpfile pattern name. . max length 128 characters; default value is "core" . core_pattern is used as a pattern template for the output filename; certain string patterns (beginning with '%') are substituted with their actual values. . backward compatibility with core_uses_pid: If core_pattern does not include "%p" (default does not) and core_uses_pid is set, then .PID will be appended to the filename. . corename format specifiers: %<NUL> '%' is dropped %% output one '%' %p pid %P global pid (init PID namespace) %i tid %I global tid (init PID namespace) %u uid %g gid %d dump mode, matches PR_SET_DUMPABLE and /proc/sys/fs/suid_dumpable %s signal number %t UNIX time of dump %h hostname %e executable filename (may be shortened) %E executable path %<OTHER> both are dropped . If the first character of the pattern is a '|', the kernel will treat the rest of the pattern as a command to run. The core dump will be written to the standard input of that program instead of to a file.
step
1) write coredump.sh script into / usr / local / directory
#!bin/bash #/proc/<pid>/maps cat /proc/$1/maps > /tmp/maps_of_$1 #coredump dd > /tmp/core_$1_$2_$3
2) Execute the following commands to configure coredump
ulimit -c unlimited echo "|/usr/local/coredump.sh %p %e %s" > /proc/sys/kernel/core_pattern
After configuration is complete, so that the application exception occurs if the trigger coredump, will crawl / proc / <pid> / maps coredump file and dump file.
test
1) Trigger coredump
root@chgao-virtual-machine:/media/new/linyao/debugging/SIGFPE# ./test Floating point exception
2) into the / tmp crawl to see if coredump files and maps
root@chgao-virtual-machine:/tmp# ls core_8124_test_8 maps_of_8124 root@chgao-virtual-machine:/tmp# file core_8124_test_8 core_8124_test_8: ELF 64-bit LSB core file x86-64, version 1 (SYSV), SVR4-style, from './test' root@chgao-virtual-machine:/tmp# file maps_of_8124 maps_of_8124: ASCII text
3) file View maps
root@chgao-virtual-machine:/tmp# cat maps_of_8124 00400000-00401000 r-xp 00000000 fc:00 57147397 /media/new/linyao/debugging/SIGFPE/test 00600000-00601000 r--p 00000000 fc:00 57147397 /media/new/linyao/debugging/SIGFPE/test 00601000-00602000 rw-p 00001000 fc:00 57147397 /media/new/linyao/debugging/SIGFPE/test 7fad5d07a000-7fad5d23a000 r-xp 00000000 08:01 268253 /lib/x86_64-linux-gnu/libc-2.23.so 7fad5d23a000-7fad5d43a000 ---p 001c0000 08:01 268253 /lib/x86_64-linux-gnu/libc-2.23.so 7fad5d43a000-7fad5d43e000 r--p 001c0000 08:01 268253 /lib/x86_64-linux-gnu/libc-2.23.so 7fad5d43e000-7fad5d440000 rw-p 001c4000 08:01 268253 /lib/x86_64-linux-gnu/libc-2.23.so 7fad5d440000-7fad5d444000 rw-p 00000000 00:00 0 7fad5d444000-7fad5d46a000 r-xp 00000000 08:01 268251 /lib/x86_64-linux-gnu/ld-2.23.so 7fad5d64b000-7fad5d64e000 rw-p 00000000 00:00 0 7fad5d669000-7fad5d66a000 r--p 00025000 08:01 268251 /lib/x86_64-linux-gnu/ld-2.23.so 7fad5d66a000-7fad5d66b000 rw-p 00026000 08:01 268251 /lib/x86_64-linux-gnu/ld-2.23.so 7fad5d66b000-7fad5d66c000 rw-p 00000000 00:00 0 7ffc833d2000-7ffc833f3000 rw-p 00000000 00:00 0 [stack] 7ffc833f5000-7ffc833f8000 r--p 00000000 00:00 0 [vvar] 7ffc833f8000-7ffc833fa000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
4) Use the gdb debugger coredump file
root@chgao-virtual-machine:/media/new/linyao/debugging/SIGFPE# gdb ./test /tmp/core_8124_test_8 GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.5) 7.11.1 Copyright (C) 2016 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>. Find the GDB manual and other documentation resources online at: <http://www.gnu.org/software/gdb/documentation/>. For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from ./test...done. [New LWP 8124] warning: the debug information found in "/lib64/ld-2.23.so" does not match "/lib64/ld-linux-x86-64.so.2" (CRC mismatch). Core was generated by `./test'. Program terminated with signal SIGFPE, Arithmetic exception. #0 0x00000000004004f3 in main (argc=1, argv=0x7ffc833f1658) at test.c:12 12 result = a / b; (gdb) info registers rax 0x2 2 rbx 0x0 0 rcx 0x0 0 rdx 0x0 0 rsi 0x7ffc833f1658 140722510435928 rdi 0x1 1 rbp 0x7ffc833f1570 0x7ffc833f1570 rsp 0x7ffc833f1570 0x7ffc833f1570 r8 0x400570 4195696 r9 0x7fad5d454ab0 140382570891952 r10 0x846 2118 r11 0x7fad5d09a740 140382566983488 r12 0x4003e0 4195296 r13 0x7ffc833f1650 140722510435920 r14 0x0 0 r15 0x0 0 rip 0x4004f3 0x4004f3 <main+29> eflags 0x10246 [ PF ZF IF RF ] cs 0x33 51 ss 0x2b 43 ds 0x0 0 es 0x0 0 fs 0x0 0 gs 0x0 0 (gdb) bt #0 0x00000000004004f3 in main (argc=1, argv=0x7ffc833f1658) at test.c:12