OpenBMC Source-Level Debugging

[Bills, Jason M]

On 1/17/2020 1:54 PM, James Feist wrote:
> On 1/14/20 5:02 AM, John Chung wrote:
>> Hi All,
>>
>> I am doing a personal study on OpenBMC recently. And I am wondering 
>> that how to do source-level debugging via gdb, especially in vscode 
>> (Not sure it is possible or not).
> 
> This is how I get gdb running, there may be (probably are) better ways:
> 
> 1. Add IMAGE_INSTALL_append +=  "gdb" to the end of your local.conf to 
> get gdb in the image.
> 2. devtool modify 'package' to modify package
> 3. scp 
> build/workspace/sources/<package-name>/oe-workdir/packages-split/<package-name>-dbg/usr/bin/.debug/<application-name> 
> onto image to get symbols.
> 4. gdb pacakge
> 5. symbol-file <file you just scpd>
> 
> Not sure about vscode usage.
> 
> -James
I had some minimal success getting remote GDB working.  Here are the 
notes that I kept:
1. Add 'IMAGE_INSTALL_append += " gdbserver"' to /local/local.conf
2. Build 'gdb-cross-arm' recipe without python
	a. If libreadline.so.7 error, 'export LD_LIBRARY_PATH=<path to 
libreadline.so.7>'
3. On Target, run 'gdbserver localhost:9999 <app to debug>'
4. On Host, run 'arm-openbmc-linux-gnueabi-gdb <app to debug with symbols>
	a. Then run 'target remote <ip>:9999'
	b. Then run 'continue' to start app on target
		
https://www.linux.com/news/remote-cross-target-debugging-gdb-and-gdbserver
https://stackoverflow.com/questions/21928876/gdb-can-not-load-source-file

I believe for step 2, I modified the PACKAGECONFIG to disable python.

Sorry that the notes are a little rough, and it's been a while since I 
tried this, so ymmv.
-Jason

> 
>>
>> If anyone has any experience or documentation, please kindly let me know.
>>
>> Very appreciated for the help.
>>
>> Thanks,
>> John
>>
>>