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Debian/Ubuntu systemd coredump调试程序Crash

news 来源：原创 2025/6/15 5:47:06

程序是通过systemd监管，当程序出现crash的时候，需要保存crash的日志，也就是coredump日志，按照一般做法设置coredump。而在安装有systemd服务的系统中一般都有systemd-coredump服务。
systemd-coredump 是 systemd 子系统中的一个工具，用于收集、处理和存储 Linux 系统中的 core dump 文件。它是现代 Linux 系统中处理进程崩溃信息的推荐方式，替代了传统的直接生成 core 文件。

systemd-coredump的主要功能

功能	说明
📦 捕获崩溃进程的核心转储	接管核心转储处理，替代传统 core 文件
🧾 保存或丢弃 core 文件	可配置是否保存到磁盘、压缩、限制大小
🗂 统一存储	所有 core 文件保存到 `/var/lib/systemd/coredump/`
🔍 提供调试接口	`coredumpctl` 命令用于列出、查看、调试 core 文件
🧱 安全性	默认以受限权限运行，不会泄露敏感信息

安装systemd-coredump服务

检查是否已安装

$ which coredumpctl
/usr/bin/coredumpctl

这里会输出coredumpctl所在的位置，而我最开始的时候，系统是没有安装coredumpctl。

安装systemd-coredump服务

$ sudo apt-get install systemd-coredump
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following NEW packages will be installed:systemd-coredump
0 upgraded, 1 newly installed, 0 to remove and 261 not upgraded.
Need to get 93.0 kB of archives.
After this operation, 374 kB of additional disk space will be used.
Get:1 https://mirrors.aliyun.com/debian-security bookworm-security/main arm64 systemd-coredump arm64 252.38-1~deb12u1 [93.0 kB]
Fetched 93.0 kB in 1s (181 kB/s)
Selecting previously unselected package systemd-coredump.
(Reading database ... 156369 files and directories currently installed.)
Preparing to unpack .../systemd-coredump_252.38-1~deb12u1_arm64.deb ...
Unpacking systemd-coredump (252.38-1~deb12u1) ...
Setting up systemd-coredump (252.38-1~deb12u1) ...Configuration file '/etc/systemd/coredump.conf'==> File on system created by you or by a script.==> File also in package provided by package maintainer.What would you like to do about it ?  Your options are:Y or I  : install the package maintainer's versionN or O  : keep your currently-installed versionD     : show the differences between the versionsZ     : start a shell to examine the situationThe default action is to keep your current version.
*** coredump.conf (Y/I/N/O/D/Z) [default=N] ? Y
Installing new version of config file /etc/systemd/coredump.conf ...
Creating group 'systemd-coredump' with GID 991.
Creating user 'systemd-coredump' (systemd Core Dumper) with UID 991 and GID 991.
Processing triggers for man-db (2.11.2-2) ...

coredump.conf --> 这里输入Y

配置coredump.conf

[Coredump]
Storage=external
Compress=yes
ProcessSizeMax=2G
ExternalSizeMax=2G
JournalSizeMax=767M
MaxUse=2G
#KeepFree=

检查core_pattern

在安装systemd-coredump服务时，已经做了对应的配置

cat /proc/sys/kernel/core_pattern
|/lib/systemd/systemd-coredump %P %u %g %s %t 9223372036854775808 %h %d

reload systemd

sudo systemctl daemon-reexec

测试

测试程序

// crash.cpp
int main() {int* p = nullptr;*p = 1;
}

编译&触发coredump

$ g++ crash.cpp -o crash
ulimit -c unlimited
./crash

检查systemd-coredump的输出

$ coredumpctl list
TIME                           PID  UID  GID SIG     COREFILE EXE                            SIZE
Wed 2025-06-11 01:49:07 BST 357407 1000 1000 SIGSEGV present  /home/pi/workspace/core/crash 35.5K

具体coredump信息

$ coredumpctl info crashPID: 357407 (crash)UID: 1000 (pi)GID: 1000 (pi)Signal: 11 (SEGV)Timestamp: Wed 2025-06-11 01:49:06 BST (2min 22s ago)Command Line: ./crashExecutable: /home/pi/workspace/core/crashControl Group: /user.slice/user-1000.slice/session-67.scopeUnit: session-67.scopeSlice: user-1000.sliceSession: 67Owner UID: 1000 (pi)Boot ID: 9f37ddcf177845c5b33baf5ede4df169Machine ID: 3193cd42b55048b38d93ded435763681Hostname: raspberrypi-CM5Storage: /var/lib/systemd/coredump/core.crash.1000.9f37ddcf177845c5b33baf5ede4df169.357407.1749602946000000.zst (present)Size on Disk: 35.5KMessage: Process 357407 (crash) of user 1000 dumped core.Stack trace of thread 357407:#0  0x000055562d490724 n/a (/home/pi/workspace/core/crash + 0x724)#1  0x00007fffb2fc7740 __libc_start_call_main (libc.so.6 + 0x27740)#2  0x000055562d490714 n/a (/home/pi/workspace/core/crash + 0x714)ELF object binary architecture: AARCH64

coredump debug

$ coredumpctl gdb crashPID: 357407 (crash)UID: 1000 (pi)GID: 1000 (pi)Signal: 11 (SEGV)Timestamp: Wed 2025-06-11 01:49:06 BST (2min 5s ago)Command Line: ./crashExecutable: /home/pi/workspace/core/crashControl Group: /user.slice/user-1000.slice/session-67.scopeUnit: session-67.scopeSlice: user-1000.sliceSession: 67Owner UID: 1000 (pi)Boot ID: 9f37ddcf177845c5b33baf5ede4df169Machine ID: 3193cd42b55048b38d93ded435763681Hostname: raspberrypi-CM5Storage: /var/lib/systemd/coredump/core.crash.1000.9f37ddcf177845c5b33baf5ede4df169.357407.1749602946000000.zst (present)Size on Disk: 35.5KMessage: Process 357407 (crash) of user 1000 dumped core.Stack trace of thread 357407:#0  0x000055562d490724 n/a (/home/pi/workspace/core/crash + 0x724)#1  0x00007fffb2fc7740 __libc_start_call_main (libc.so.6 + 0x27740)#2  0x000055562d490714 n/a (/home/pi/workspace/core/crash + 0x714)ELF object binary architecture: AARCH64GNU gdb (Debian 13.1-3) 13.1
Copyright (C) 2023 Free Software Foundation, Inc.
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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.
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Type "show configuration" for configuration details.
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Reading symbols from /home/pi/workspace/core/crash...
(No debugging symbols found in /home/pi/workspace/core/crash)
[New LWP 357407]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/aarch64-linux-gnu/libthread_db.so.1".
Core was generated by `./crash'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x000055562d490724 in main ()
(gdb) bt
#0  0x000055562d490724 in main ()
(gdb) quit

自定义service配置

[Unit]
Description=application
After=custom.service
Requires=xxxx.service[Service]
LimitCORE=infinity
LimitSTACK=infinity
Type=simple
ExecStart=/custom/app/custom
Restart=on-failure
TimeoutStopSec=30s
WorkingDirectory=/custom[Install]
WantedBy=multi-user.target

设置项	说明
`LimitCORE=infinity`	允许 systemd 启动的程序生成 core dump
`WorkingDirectory`	core 文件会默认保存到这里（如果未被 systemd-coredump 截获）
`Restart=on-failure`	保证崩溃时自动重启进程（但不影响 core dump）