The debugging tag has no wiki summary.
16
votes
4answers
2k views
Kernel Hacking Environment
I have been working in embedded OS like uCOS, ThreadX. While I have coded apps in Linux, now I’m planning to start learning Linux Kernel. I have few questions regarding the environment.
Which is ...
10
votes
4answers
2k views
How can I debug a Suspend-to-RAM issue on Linux?
I'm hoping to get experience-based suggestions on how to go about debugging suspend-to-RAM issue. Advice specific to my situation(detailed below) would be great, but I am also interested in general ...
8
votes
5answers
3k views
Can we get compiler information from an elf binary?
Is there some chance to know how a binary was built, under Linux? (and or other Unix)
Compiler, version, time, flags etc...
I looked at readelf and couldn't find much, but there might be other ways ...
8
votes
2answers
656 views
strace for library calls
I know of strace, which is super handy for watching system calls. Is there an equivalent that can trace calls to external libraries?
For example, I'm trying to debug some SSLeay misbehavior with a ...
7
votes
3answers
349 views
Best practise to diagnose problems [closed]
As Linux/Unix users, we run into problems frequently. And after long hours of problem solving, we develop the skill of debugging.
Now, what are good principles, methods or best practises when trying ...
6
votes
2answers
2k views
How to debug a suspend problem?
I used to have Fedora 14 installed on this HP Compaq 610, and the suspend feature worked fine. Now that I've installed Scientific Linux 6.1 suspend doesn't work anymore. How do I debug/fix it?
6
votes
2answers
1k views
How do I debug a kernel module in which a NULL pointer appears?
I have a custom kernel module that I compiled from this patch that adds support for the logitech G19 keyboard among other G series devices. I compiled it just fine against Ubuntu's maverick kernel's ...
6
votes
2answers
171 views
bash: escape individual lines from `-x` echoing
In bash, when running with the -x option, is it possible to exempt individual commands from echoing?
I'm trying to make the output as neat as possible, so I am running certain parts of my script in a ...
6
votes
2answers
662 views
How can I find what is interfering with CTRL+F?
I'm running LinuxMint12 with Gnome with Cario-Dock and I have a logitech G15 keyboard. I set up a bash script with the extra keys to take the active window, resize it, and move it to a specific ...
6
votes
1answer
713 views
How to debug system freeze?
I'm experiencing strange bug when I close lid of my laptop - system freezes (no reaction on keys, no response form ssh) hard and displays some strange colour effects. The kernel log (after reboot) ...
6
votes
1answer
130 views
Sending commands to dbx from Vim
Using this information, I've been able to debug code using dbx and display the code from within Vim.
What would be really cool is if I could send commands (step, next, print, stop in ... etc) to dbx ...
5
votes
5answers
1k views
How to track/fix a memory-related issue in a large C/C++ code on *nix systems
What strategy you use while tracking a memory-related issue? What tools do you use (open source as well as proprietary) to identify memory leaks, memory corruption etc? How would you track memory ...
5
votes
3answers
2k views
Linux network troubleshooting and debugging
From time to time Linux and Unix users faced with various network problems. Many of these problems are presented here and at some others troubleshooting forums, but the are very concrete and contains ...
5
votes
2answers
833 views
Dump process core without killing the process
Is there a way to get a core dump (or something similar) for a process without actually killing the processes? I have a multithreaded python process running on an embedded system. And I want to be ...
5
votes
1answer
113 views
Debugging lock-up - systemd loses my logs
Ever since I have "upgraded" to systemd on Arch Linux, I keep losing logs when an unexpected lockup happens. I hit the same log-losing issue one month ago and just hit the issue again. There are also ...
5
votes
2answers
270 views
Unclaim a device
So I am using Ubuntu and trying to use some hardware which I had some problems with before.
The problem before was that the company who made my hardware sold their internal parts to another company ...
4
votes
2answers
1k views
Can gdb debug suid root programs?
I wrote a program that calls setuid(0) and execve("/bin/bash",NULL,NULL).
Then I did chown root:root a.out && chmod +s a.out
When I execute ./a.out I get a root shell. However when I do gdb ...
4
votes
4answers
1k views
Debugging Linux machine freezes
I have 15 identical Linux RH 4.7 64-bit severs. They run cluster database (cluster is application level). On occasion (every month or so) a random box (never the same though) freezes.
I can ping the ...
4
votes
5answers
325 views
Unpredictable memory explosions
The main server at my company has recently been having a lot of downtime. For reasons that neither I nor the other admins can determine, it has random (VERY sudden) explosions in memory. It becomes ...
4
votes
1answer
2k views
how can I make cron run a job right now, for testing/debugging? without changing the schedule!
I have a cron job that is scheduled to run everyday, other than changing the schedule, is there any other way to do a test run of the command right now to see if it works as intended?
4
votes
1answer
736 views
What is the difference between /proc/self/stack and output from pstack?
I have been looking through the documentation for /proc and the "stack" object being a new'ish object in proc, I have also looked through the kernel commit to create it -- however the documentation ...
4
votes
2answers
277 views
How to debug an inserted kernel module?
I would like to debug a loaded kernel module I don't have the source code to; I suspect it's a virus. Is there a way to feed it into GDB for analysis?
4
votes
2answers
1k views
How to enable crash reports/core dumps/stack trace logging globally?
Crashing bugs can be the most annoying ones, leading to data loss, downtime and frustrated users. It would be good if applications crashed less.
Because of the complexity of the machine context, ...
3
votes
3answers
497 views
Debugging ethernet before NFS boot
I'm trying to boot Linux from U-boot on an embedded ARM board using a filesystem on a remote machine served via NFS. It appears that the ethernet connection is not coming up correctly, which results ...
3
votes
1answer
337 views
Capture and log GDB backtraces without stopping the process
First, a brief description of the situation: a computer sits hidden near a display in a gallery of some sort, acting as the silent workhorse for a piece. Despite its programmer's best intentions the ...
3
votes
2answers
196 views
Shell script debugging
I was wondering if there is an IDE that would allow me to define an ssh connection to a remote host, connect, and locally debug a script running remotely (kind of like you can debug a remote Java app ...
3
votes
1answer
115 views
How to debug a buggy running GUI application?
Suppose the GUI applications are not given names in its GUI, so you don't know what to check in 'ps -A', i.e. the nameless applications in the task bar. How do I know which GUI application belong to ...
3
votes
2answers
429 views
Unix/Linux C++ debugger that supports STL containers?
Currently I am using gcc-4.3.6 and Eclipse IDE for c++ development. I want to debug my project in Eclipse with gdb. I am having a hard time debugging code when it contains STL containers. Also I am ...
3
votes
2answers
1k views
Sound Problems with pulseaudio
The overall question that my whole problem is kind of based on is regarding sound in linux. Should I be using alsa or pulse or what?
I'm using pulse at the moment and this is my problem: I was in the ...
3
votes
2answers
857 views
Missing separate debuginfo for - GDB
I have mentioned -g option along with -Wall in the Makefile.
When I run gdb onlineSunday, I get:
Missing separate debuginfo for /usr/lib64/kde4/plugins/imageformats/kimg_dds.so
Try: zypper install ...
2
votes
1answer
494 views
How does a debugger work in Linux?
How does a debugger work in Linux? How does it gets 'attached' to an already running executable or process. I understand that compiler translates code to machine language, but then how does debugger ...
2
votes
2answers
168 views
Is there a way to find out which program is segfault-ing?
I have a Busybox/Linux system where a mystery program is segfaulting rarely. Is there a way to find which program is doing this?
2
votes
1answer
79 views
Submitting bug reports for Arch Linux
I come from Ubuntu and when things crashed I could collect the relevant information and submit a bug report. Is there an easy or preferred way to do this in Arch Linux after an application crashes?
2
votes
1answer
402 views
Kernel and QEMU : Unable to mount root fs error
I am trying to run a distro in the virtual disk image with a custom kernel,so that I can experiment and debug the kernel. I followed this to make a disk image and then install Debian to it. Now I ...
2
votes
1answer
618 views
How to debug csh scripts?
My lab uses csh scripts to run jobs. It is usually difficult for me to debug a shell script, so I'm wondering if there is a csh debugger I can use.
I know there are some flags like -x or -v that can ...
2
votes
1answer
186 views
Installing slime and emacs
I'm trying to install SLIME on Fedora 17 so that I can do some lisp.
Here is what I downloaded:
http://www.common-lisp.net/project/slime/#downloading
The CVS Snapshot link.
I have a .emacs file:
...
2
votes
3answers
278 views
Kernel debugging
I would like to study the flow of some linux device drivers and some minimal flow of kernel (threading cum context switching and interrupt management).
How can I debug the linux kernel? What are the ...
2
votes
1answer
179 views
How can I figure out why gnome-panel is frequently misbehaving?
On my system (Debian Lenny AMD64), gnome-panel seems to act up now and again. I've not found a way to force it to happen, but it seems to be related to launching processes. Basically, I launch some ...
2
votes
1answer
403 views
Debugging Linux Kernel with QEMU
I was trying to study the debugging of kernel using QEMU. I tried initially and failed due to the fact that there was no virtual file system. The answers to this post suggests that there should be a ...
2
votes
1answer
65 views
Start and stop multiple executable for easy debugging
I'm debugging a networking project, which involves interacting of 3 programs, ie a server, two different clients. However I find it difficult to start and stop them for debugging. Some methods I have ...
2
votes
1answer
297 views
Disable browser logging output to console
I'm currently using Ubuntu 11.04 and I'm running into a really annoying issue while developing for web. I'm rather new to Ubuntu, coming from FreeBSD where I never encountered an issue like this, so ...
2
votes
0answers
40 views
kgdb not returning control to gdb
I've compiled a kernel with kgdb support and I'm trying to debug it. I have two machines running, a debug machine (running the kgdb kernel) and the machine I'm using to debug it. They are connected ...
2
votes
0answers
79 views
How to find where driver.mod.c links to?
I'm trying to port the webcam composite gadget from kernel 2.6.37 to 2.6.32. I don't have a choice on this since I depend on other drivers and a SDK which only compile for this version.
My train of ...
2
votes
0answers
418 views
Linux kernel slab usage growing on embedded system
I'm in the process of QA/debugging a project on a custom embedded linux system. The problem we're VERY tight on memory, and even a couple megs can cause issues with our software.
What I'm seeing ...
2
votes
1answer
434 views
Dump Page table layout (KERNEL CONFIG)
While configuring kernel for debugging found this option:
CONFIG_X86_PTDUMP: Export kernel
pagetable layout to userspace via
debugfs
Does this mean RAM page-table layouts ? any guides on how ...
1
vote
2answers
1k views
How to proceed solving ppp connection problems?
I got an embedded system trying to create a ppp connection using a GSM modem. However the connection is never established and all I get is this error message in syslog:
Oct 12 08:38:48 pppd[451]: ...
1
vote
1answer
121 views
Killed `rm` and `cp` on nfs share
I am just testing an rsnapshot installation on my laptop which should backup to a NAS mounted via nfs on my laptop.
On one test rsnapshot died with a cp -al problem (i.e. a problem with hard links) ...
1
vote
1answer
32 views
How can I force my wifi to connect to a G-band channel?
I'm trying to debug a buggy wireless card and would like to force my Linux computer to connect using one of the g-band channels. How can I achieve this?
1
vote
1answer
171 views
How to avoid overflowing the kernel printk ring buffer?
I'm trying to debug a linux driver and a particular piece of code is behaving very strangely. In order to see what's going on I've filled the code with printk statements so I can see exactly what the ...
1
vote
1answer
353 views
How do I fix a noisy input device (Internal Mic)? snd_hda_intel - debug included
As the title says, I'm having trouble with a very noisy audio input device - the internal mic or any plugged in mics.
So far I've narrowed it down to an problem in ALSA since my debug info is showing ...
