is a process of finding and reducing the number of bugs, or defects, in a computer program, thus making it behave as expected

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5
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1answer
219 views

linux mint hangs - how to find a reason?

My Linux Mint system (17 Cinnamon, lenovo g565) hangs up frequently during work (say, 2-4 times a day). It usually looks like a white or black screen (or off if the lid was closed). CPU seems to be a ...
4
votes
1answer
1k views

My Debian freezes

I installed a fresh Debian 7 install, but it freezes from time to time, and when it happens (quite often indeed) only the mouse can move around but everything is blocked. All I can do is restart. I ...
3
votes
1answer
66 views

Debugging info in linux kernel - how does it work?

I have found that I can compile linux kernel with some flags adding debugging support like CONFIG_DEBUG_INFO. These options while useful in debugging are also required by some utilities like ...
3
votes
1answer
146 views

detect process that executes portscans

I have to administer an ubuntu 12.04 server, where there seem to go portscans to the whole subnet. How can I find out the process that does the scans? pstree init─┬─acpid ...
2
votes
1answer
97 views

Why is my Compose key not being passed to Synergy?

The key that I assign to the compose key (right Alt) is not passed to the remote computer by Synergy. I don't know if it's a problem with Synergy or with X, but my guess is that the compose key is ...
2
votes
1answer
382 views

SystemTap simple demo fails

Started learning SystemTap using RedHat's manual. Here is the example I'm trying to run. While executing stap open.stp I got the error: [root@ror6ax ~]# stap open.stp semantic error: while resolving ...
1
vote
1answer
101 views

“rcu_preempt detected stalls on CPUs / tasks” message appears to continue

My board continues to display the message below. The terminal does not have any input. What is it with the following message, which I know? (T, g, c, q ...) What is the cause of this phenomenon? ...
1
vote
1answer
645 views

How to debug an installed Qt5 library with GDB?

Background: I am programming with Qt5 and want to debug the core Qt5 libraries on Debian using GDB. I have installed all the necessary -dev and -dbg packages. When I try to debug, GDB complains that ...
1
vote
1answer
203 views

Which log files do I look at to debug copy/paste and Klipper?

Short Version What log files do I look at to monitor copy/paste actions? And what logs do I look at to monitor all Klipper actions? Long Version After using my desktop for a while (could be a few ...
1
vote
1answer
279 views

What's a good way to debug issues with X forwarding over ssh where just some applications won't run?

As far as I understand it, X forwarding is usually pretty simple. Once I can run some things like xeyes or gimp over ssh, complex applications like firefox/iceweasel should also be able to run. ...
0
votes
1answer
35 views

Debugging: OwnCloud horribly slow

I am trying to figure out why my OwnCloud installation stalls of 10s of seconds before it runs again for 10s of seconds normally. What kind of debugging can I enable on OwnCloud (server+client), so I ...
0
votes
1answer
41 views

Syntax error: Unterminated quoted string. Cannot find error

I'm writing a script to parse a larger file into usable data. I will attach the script below. The script was not running as I wanted and I thought it might have been the if/then statement I used, but ...
0
votes
1answer
25 views

SystemTap simple demo fails - Ubuntu 14.04

Started learning SystemTap using RedHat's manual. Here is the example I'm trying to run. While executing stap open.stp I got the error: [root@ror6ax ~]# stap open.stp semantic error: while resolving ...
0
votes
1answer
95 views

Linux Mint 17.1 Mate stops responding

I was using LM 17.1 Mate version quite smoothly until one day I found my desktop wallpaper had changed to the original. Then after refreshing for 2nd time it keeps on refreshing and it seems that my ...
0
votes
1answer
95 views

Trying to use KDBG, but it produces error 11

I am trying to start kdbg on Ubuntu, but it produces this error message: MNG error 11: function is invalid at this point ; chunk MHDR; subcode 0:0 MNG error 11: function is invalid at this point ; ...
0
votes
1answer
1k views

How do I get debug information from rsyslog?

I followed the directions from: http://www.rsyslog.com/doc/debug.html I put the following in /etc/rsyslog.conf: $DebugLevel 2 $DebugFile /root/RSYSLOG.txt then I try: kill -USR1 `cat ...
0
votes
1answer
77 views

Getting Sublime + xDebug to work on Debian

I have been trying to get sublime and xdebug to work on debian, but have had no luck. I can't seem to find any debian specific guides. I have tried using the ubuntu based guides, but they don't work ...
4
votes
0answers
306 views

Is there an equivalent of addr2line on AIX system?

I'd like to debug proftpd on AIX and according to the documentation, addr2line is a usefull binary to identify what is not working. Extract of proftpd debugging documentation: The key here for ...
3
votes
0answers
180 views

An obscure autotools error with Epson iscan project

I'm seeing the following error when attempting to build iscan using the master branch on Debian wheezy. This project provides support for Epson scanners, in cases when SANE doesn't. This project ...
3
votes
0answers
174 views

Understanding line numbers reported when using eval

Okay, so I'm stuck working with a shell script that needs to use eval (I know, I know, ultimate evil etc…) however I'm having difficulty debugging some of the line numbers being thrown out by errors. ...
2
votes
0answers
37 views

Network debugging: Sudden rise in packet loss and latency

My laptop sees a sudden rise in packet loss and latency (from 0.0%, 1ms to 70%, 2000ms). It remains even after resuming from suspend-to-ram. It remains after: sudo killall wpa_supplicant sudo ...
2
votes
0answers
29 views

Significance of Linux kernel's default_console_loglevel

What is the significance of default_console_loglevel in Linux? Commonly I see it described as the default value of console_loglevel. However, what that means I haven't seen explained anywhere. ...
2
votes
0answers
126 views

How can I monitor the interactions of an application with dbus?

I think the title says it all. I have a set of applications, I want to montior any and all interactions of the applications with dbus. The things I've played with don't seem to have a way of focusing ...
2
votes
0answers
213 views

What is the correct way to fix the configure error: “Requested 'libdrm_nouveau >= 2.4.33' but version of libdrm_nouveau is 0.6”?

This issue came up when trying to assist a user with the questions: What are the required build dependencies of mesa for Debian-based distros? and How do I backport Mesa on Debian Wheezy?. Mesa on ...
2
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0answers
628 views

How should I enable the trace log for ALSA hda_unsol_event?

I have reported an ALSA kernel bug and have been asked to "enable tracepoints" and "check the response of hda_unsol_event". I was directed to the kernel docs for instruction, which say: Except ...
2
votes
0answers
63 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
207 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
950 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 ...
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0answers
71 views

Linux Kernel module Remote Debugging with GDB + KGDB, Remote 'g' packet reply is too long

I am trying to remotely debug Linux Kernel and I am having issues. My setup: Target machine with Ubnutu Linux with my custom kernel 4.3 which I built with debugging information and KGDB. ...
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0answers
117 views

ath0 wi-fi connection breaks

Can't hold wi-fi connection in hostapd mode. Sometimes it's good, sometimes not, yesterday all day wi-fi works, today no chance even to connect. % more /etc/rc.conf wlans_ath0="wlan0" ...
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vote
0answers
206 views

Transfer file to pc from embedded linux device via serial communications

I'm working on an AT91SAM9G20. I'm connected to AT91SAM9G20 via the debug port using rs232 serial communications. It has Linux version 3.4.8 but does not appear to have any of the common file ...
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0answers
450 views

How to display printk messages filtered by level as they come?

I wrote a hello word module that performs a printk when it is loaded in level ALERT and another printk when it is released with level INFO: #include <linux/module.h> #include ...
1
vote
0answers
2k views

What does “Cannot make/remove an entry for the specified session” mean?

Instead of logging me in, PAM greets me with the message "Cannot make/remove an entry for the specified session" after I enter the password. What entry is it talking about (and what session)? The ...
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0answers
244 views

Why is the service unavailable the second time?

How can this happen? /volume1/homes/me $ tdtool --list /volume1/homes/me $ tdtool -e 44 Learning device: 44 - Could not connect to the Telldus Service /volume1/homes/me $ tdtool --list Error fetching ...
1
vote
0answers
387 views

How to trace calls to library from library?

I have an program that calls libcurl, and libcurl calls libgssapi_krb5. If I want to debug calls to libcurl, then ltrace works. But now I want to debug calls to libgssapi_krb5, then ltrace ...
0
votes
0answers
8 views

Stracing a kernel shut down?

I'm on Linux 4.2.0, the Ubuntu Wily HWE kernel for Ubuntu 14.04 (which is what I'm running). There's a nasty bug on MacBook 11,4 and 11,5 models where the laptops won't actually ever shut off, they ...
0
votes
0answers
10 views

How to debug a bash script in a qemu-arm chroot

I'm running a debian debootstrap script which creates an arm system. However, the script fails at some point and the error message does not really help. So I'll have to do some more debugging which is ...
0
votes
0answers
10 views

Does Manjaro Linux have a debug packages

One of my biggest frustrations with Arch Linux is the need to recompile half my OS every few weeks in order to provide meaningful bug reports to upstream projects. Most other distributions provide ...
0
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0answers
31 views

printk does not prints in terminal

I inserted some printk in kernel 3.15.1 functions such as theese: in fs/read_write.c in function read(): printk("Ata: Im in fs/read_write.c and in function read"); in same file in function ...
0
votes
0answers
20 views

OpenVPN Connection without disabling Internet debugging

I've recently configured OpenVPN on my server (CentOS 7) and been configuring it for hours now and everything seems to work fine except that when I connect using a client machine I cannot access the ...
0
votes
0answers
12 views

Breakpoint in dynamically-linked libraries in Linux

Suppose you debug a Linux application and put a break-point into a function defined by a dynamically-linked library used by the application. Will that break-point stop any other application that makes ...
0
votes
0answers
27 views

Cannot telnet to Postgresql Forwarded Port

I'm trying to portforward a PostgreSQL port using my DLINK ADSL Router. I have the following IP addresses. Public Internet IP 197.321.321.32 PostgreSQL 192.123.123.12:5432 (Port To ...
0
votes
0answers
27 views

How can I display \n as new lines in multitail?

I am using multitail to monitor logs while I program. I really like this tool. However, it is hard to use it to view object output in a php error log because new line characters \n are not processed. ...
0
votes
0answers
673 views

Kernel panic : Kernel offset disabled

I was trying to install the linux-next kernel in my system with the following steps. Copied the existing configuration file from /boot to the root of source directory Updated the .config file with ...
0
votes
0answers
40 views

Attempting to use LogLevel debug to investigate server issue

I am currently running a WordPress Multisite installation with a number of websites active. I have started getting large volumes of the following error message in my error log: Request exceeded the ...
0
votes
0answers
121 views

Can't install additional debug infos in the CentOS 6.7

I am attempting to debug coredump of the some application on the latest CentOS 6.7 and gdb gives me hints that some debug infos are missing, for example: Missing separate debuginfo for ...
0
votes
0answers
288 views

How to change the console_loglevel in linux?

I read at multiple places (e.g. here http://elinux.org/Debugging_by_printing), that you can change the console log level by echoing an integer to /proc/sys/kernel/printk. If that worked shouldn't the ...
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0answers
52 views

How to debug freeze at start, output of syslog

Every now and then, my computer freezes while starting. I can see some "Oops" in /var/log/syslog, but from there I am not sure what to do to try and fix the problem. Jun 5 12:47:40 fulla kernel: [ ...
0
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0answers
72 views

How to debug : Screen starts blanking after running wget

My system is currently running Cubieez 2.2, a Debian image for CubieTruck. My bash script is tasked with downloading driver files from a server to a specific folder through wget. I've tested this bash ...
0
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0answers
99 views

Linux unresponsiveness

I'm using a Packard Bell EasyNote laptop (4GB RAM, 500GB HDD) with Arch Linux and xmonad. My problem is that machine becomes fully unresponsive or obtains a large lag. Sometimes when I only have a ...