When GDB debug exe with dump , it can't load symbols

[LiangJy123]

Hi ,
When I use GDB to debug my exe in Mariner, I meet a problem as the title suggests.

The core dump file is match the executable file.

The same operation in Ubuntu2204 is normal.

Another strange thing is the dump name genarated in Mariner.

Core pattern is "/corefile/core-%e-%p-%t".
%e means executable file name without path.
But the dump name is "core-sudo-xxx-xxx" .
"sudo" is not my executable file name.

So is the GDB not work normally in this situation ?

System info:
Linux cbl-mariner-HFPKyCC2mFvu 5.15.41.1-1.cm2 #1 SMP Sat May 28 19:48:23 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

[mfrw]

Hi @LiangJy123 can you please give use some more details; like the output of cat /etc/os-release & also the version of gcc & gdb.
Did we add the -g option to gcc while compiling.
Also, can we please try running without the sudo prefix. I suspect, the perfix sudo is causing it to show up in the corefile name.

For reference:

[LiangJy123]

Hi @mfrw , thank you for your reply.

I'm sure using gcc with -g option when compiling.
It looks well on your screenshot.

But my result is not same as yours , there is no dump created without using sudo .
Is there a permission mistake with current user ?

os-release

NAME="Common Base Linux Mariner"
VERSION="2.0.20220625"
ID=mariner
VERSION_ID="2.0"
PRETTY_NAME="CBL-Mariner/Linux"
ANSI_COLOR="1;34"
HOME_URL="https://aka.ms/cbl-mariner"
BUG_REPORT_URL="https://aka.ms/cbl-mariner"
SUPPORT_URL="https://aka.ms/cbl-mariner"

gcc

Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/11.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ./configure --host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --program-prefix= --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/var/lib --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu --enable-languages=c,c++,fortran --disable-multilib --disable-bootstrap --enable-linker-build-id --enable-plugin --enable-default-pie --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 11.2.0 (GCC)

gdb

GNU gdb (GDB) 11.2
Copyright (C) 2022 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.

[mfrw]

But my result is not same as yours , there is no dump created without using sudo .

@LiangJy123 I think a few pointers that I suspect might be the cause of this:

• Is our /corefile dir writeable by the user that is running the program?
• Can we try the latest version of Mariner VERSION="2.0.20220617"

I tried to reproduce the issue using the latest release, but could not.

Reference:

Feel free to reachout offline if we still get the issue :)

[LiangJy123]

Thanks for your help @mfrw .
It works for me when changing "/corefile" dir to be writeable.
Without using sudo , GDB works well.

It's a common issue and forgive me for not being very familiar with Linux .

By the way , I am interesting with Mariner and is there any document about how to build a custom kernel module on Mariner ?

[mfrw]

There should not be any special steps involved in building a kernel module on Mariner.
The normal steps which we follow on any standard distro should be applicable here as well.