topic Re: GDB for i.MX Linux userspace and Eclipse integration in i.MX Processors

GDB for i.MX Linux userspace and Eclipse integration

AdrianGancev — Mon, 30 Apr 2012 17:33:16 GMT

General Debug Models and Mapping on GDB
General Requirements
Building latest GDB
Using GDB - first steps
Other Runtime Analysis Tools for Linux
Using the ECLIPSE Front End

General Debug Models and Mapping on GDB

CROSS: ELF on host, agent on target

- native agent runs on target for run control functions

- cross debugger runs on host for elf parsing and user interface

- communication over serial or ethernet

Pros: sources are not required on target

the agent adds minimal overhead on target

can be integrated with a visual front end

Suitable for intensive debugging of large amount of code.

Can be used without an OS on target.

Terminology: native agent = gdbserver, cross debugger = gdb

NATIVE: ELF on target

- both native debugger and agent run on target

- elf parsing, user interface and run control are all performed on target

Pros: doesn’t need additional connection with a host

doesn’t require a host debugger aware of target architecture

General Requirements

debugger/agent awareness of target architecture and OS

The application must be built with debug information

gcc: -g / -ggdb / -gdwarf-2

as: -g / -gdwarf-2 or -gdwarf2

As little optimizations as possible

gcc -O0

Availability of sources

The application must not interfere with debugger mechanisms

Un-stripped target libraries (Linux: ld.so, libthread-db.so, libpthread.so)

(uncheck strip options on LTIB Target Image Generation menu)

Building latest GDB

Download the tarball, take the latest version (now 7.4) from http://ftp.gnu.org/gnu/gdb

Have cross gcc in PATH

Build cross version

- Configure --target=$TARGET --prefix=<install destination>

- Build

- Install

Example- full commands listing for i.MX6:

$ export PATH=$PATH:/opt/freescale/usr/local/gcc-4.4.4-glibc-2.11.1-multilib-1.0/arm-fsl-linux-gnueabi/bin/

$ export TARGET=arm-fsl-linux-gnueabi

$ ./configure --target=$TARGET --prefix=/usr/local/gdb-7.4-arm-fsl-linux-gnueabi

$ make

$ sudo make install

Clean the build folder

$ make distclean

$ find . –name config.cache|xargs rm

… or better remove the entire source folder and uncompress the tarball again

Build native version (including gdbserver)

- Select target architecture and runtime (CFLAGS)

- Copy libtermcap in cross gcc runtime folder (one time operation per runtime)

- Configure --build=$MACHTYPE --host=$TARGET --prefix=<install destination>

- Build

- Install

Example- Full commands listing for i.MX6:

$ export CFLAGS="-march=armv7-a -mfpu=neon -mfloat-abi=softfp"

$ sudo cp <rootfs>/usr/lib/libtermcap.* /opt/freescale/usr/local/gcc-4.4.4-glibc-2.11.1-multilib-1.0/arm-fsl-linux-gnueabi/arm-fsl-linux-gnueabi/multi-libs/armv7-a/neon/lib

$ ./configure --build=$MACHTYPE --host=$TARGET --prefix=<rootfs>/usr/local/gdb7.4

$ make

$ sudo chmod a+w <rootfs>/usr/local/

$ make install

Using GDB - first steps

CROSS

Run agent on target

$ gdbserver :port <myapp>

Run debugger on host

$ my_built_cross_gdb

In GDB, use commands like:

file <myapp> - specify the debugged file

set sysroot <target_root_fs> - for library discovery

(set solib-search-path and solib-absolute-prefix <target_root_fs>/lib – for gdb-6.6)

target remote <target-IP>:<port> - connect with agent

NATIVE

Run debugger on target

$ gdb <myapp>

Use "set substitute-path <build-path> <actual-path>" for path mapping

Use gdb commands like the following and learn the highlighted shortcuts:

break <symbol>

break <file>:<line>

continue/run (note the differences!)

list

info thread

thread <id>

backtrace

frame

Other Runtime Analysis Tools for Linux

Check <fsl-arm-toolchain>/…/debug-root/usr/binfolder for pre-built target tools:

strace, strace-graph

ltrace

duma (Detect Unintended Memory Access)

dmalloc

Using the ECLIPSE Front End

Install JRE (> 1.5) and add it in the PATH. Download it from http://www.oracle.com/technetwork/java/javase/downloads/index.html

Install the latest ECLIPSE for C/C++ developers from http://www.eclipse.org

Run ECLIPSE and

o Create a project:

- Create a Makefile Project with Existing Code

- Choose Cross GCC

- Optional: Configure paths to build tool in Project Properties

o Configure a debugger (and remote system):

- Create a Debug Configuration of type C/C++ Remote Application

- Use GDB/DSF Manual Remote Debugger Launcher

- Specify cross gdb in Debugger/Main tab

- Specify a gdbinit file in Debugger/Main tab that contains:

set sysroot <rootfs>

- Configure target IP and gdbserver port in Debugger/Connection tab

o Prepare the target for debugging and start debugging

- Run gdbserver on host

- Try start from entrypoint mode

- Try attach to process mode

-- End --

Re: GDB for i.MX Linux userspace and Eclipse integration

PeterChan — Mon, 22 Oct 2012 02:41:55 GMT

Very helpful information!

I follow the steps for i.MX233 and they also work. Here is the my command list to build the i.MX233 GDB cross debugger.

$ export PATH=$PATH:/opt/freescale/usr/local/gcc-4.1.2-glibc-2.5-nptl-3/arm-none-linux-gnueabi/bin

$ export TARGET=arm-none-linux-gnueabi

$ ./configure --target=$TARGET --prefix=/usr/local/gdb-7.5-arm-none-linux-gnueabi

$ make

$ sudo make install

Thanks,

Peter

Re: GDB for i.MX Linux userspace and Eclipse integration

OtavioSalvador — Mon, 22 Oct 2012 05:37:58 GMT

To avoid all this manual steps you can take a look in Yocto; it is capable of build the development sysroot and toolchain as you wish.

This is how we've doing for customers.

I sent a video here today at https://community.freescale.com/message/304134#304134

Regards,

Re: GDB for i.MX Linux userspace and Eclipse integration

fishzheng — Fri, 14 Jun 2013 04:28:41 GMT

I compiled one native gdb for iMX6, but it will crash as following:

(I tried version gdb-7.4, gdb-7.4.1, and gdb-.76, I got the same result.)

usr/local/gdb-7.6/bin$ ./gdb --version

Segmentation fault

Then I check the coredump by this segmentation fault, it show:

sudo /usr/local/gdb-7.6-arm-fsl-linux-gnueabi/bin/arm-fsl-linux-gnueabi-gdb ./gdb ./core

GNU gdb (GDB) 7.6

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 "--host=i686-pc-linux-gnu --target=arm-fsl-linux-gnueabi".

For bug reporting instructions, please see:

<http://www.gnu.org/software/gdb/bugs/>...

Reading symbols from /home/nfs/usr/local/gdb-7.4/bin/gdb...done.

[New LWP 670]

Core was generated by `./gdb --version'.

Program terminated with signal 11, Segmentation fault.

#0 0x2ab0fc94 in ?? () from /home/nfs/lib/libtermcap.so.2

(gdb) bt

#0 0x2ab0fc94 in ?? () from /home/nfs/lib/libtermcap.so.2

#1 0x2ab1003c in tgetnum () from /home/nfs/lib/libtermcap.so.2

#2 0x003b4aa4 in ?? ()

#3 0x003b4aa4 in ?? ()

Backtrace stopped: previous frame identical to this frame (corrupt stack?)

(gdb) quit

Re: GDB for i.MX Linux userspace and Eclipse integration

fishzheng — Fri, 14 Jun 2013 05:54:02 GMT

More details. Only gdb will crash, and others gdbserver and run will work normally.

root@Target /mnt/nfs/usr/local/gdb-7.6/bin$ ./gdb --version

Segmentation fault

root@Target /mnt/nfs/usr/local/gdb-7.6/bin$ ./gdbserver --version

GNU gdbserver (GDB) 7.6

gdbserver is free software, covered by the GNU General Public License.

This gdbserver was configured as "arm-fsl-linux-gnueabi"

root@Target /mnt/nfs/usr/local/gdb-7.6/bin$ ./run --version

GNU simulator (GDB) 7.6

Re: GDB for i.MX Linux userspace and Eclipse integration

AdrianGancev — Wed, 19 Jun 2013 08:00:42 GMT

Run strace ./gdb and you'll see the reason of the crash. It's usually a missing file, /etc/termcap, so you can fix the problem as it follows:

$ touch /etc/termcap

Re: GDB for i.MX Linux userspace and Eclipse integration

fishzheng — Thu, 20 Jun 2013 08:55:12 GMT

Cool, it works.

Thanks.

root@TARGET /mnt/nfs/usr/local/gdb-7.6/bin$ ./gdbserver --version

GNU gdbserver (GDB) 7.6

gdbserver is free software, covered by the GNU General Public

License.

This gdbserver was configured as "arm-fsl-linux-gnueabi"

root@TARGET /mnt/nfs/usr/local/gdb-7.6/bin$ ./gdb --version

Segmentation fault

root@TARGET /mnt/nfs/usr/local/gdb-7.6/bin$ mount -o remount,rw /

root@TARGET /mnt/nfs/usr/local/gdb-7.6/bin$ touch /etc/termcap

root@TARGET /mnt/nfs/usr/local/gdb-7.6/bin$ ./gdb --version

GNU gdb (GDB) 7.6

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 "arm-fsl-linux-gnueabi".

For bug reporting instructions, please see:

<http://www.gnu.org/software/gdb/bugs/>.

On Wed, Jun 19, 2013 at 4:02 PM, AdrianGancev <admin@community.freescale.com

Re: GDB for i.MX Linux userspace and Eclipse integration

fatalfeel — Thu, 14 Jan 2016 17:41:50 GMT

kgdb + eclipse + arm gdb

Programming Guide: KGDB + Eclipse debug Kernel on i.mx6 Android

openocd + eclipse + arm gdb

Programming Guide: OpenOCD with Eclipse debug u-boot & kernel on i.mx6