Hi all,

With some investigation, there is an example to explain how to do remote 
debug.

Also file [YOCTO #9481] for document.

Hi Andreas,

Would you please have a look the example, to see if it could fit your case.

Example:

1. Build a image with gdbserver and gzip installed. The gzip
    is the debug binary. Append the following to local.conf
...
IMAGE_INSTALL_append = " gdbserver gzip"
...

$ bitbake core-image-sato

2. Build gdb-cross for remote debug on host

$ bitbake gdb-cross-i586

3. start qemu

$ runqemu qemux86 core-image-sato

4. On host side, create symlink /usr/src/debug to
    ${BASE_WORKDIR}/${MULTIMACH_TARGET_SYS} which the
    location of sources is /usr/src/debug.

$ ln -snf /TOPDIR/tmp/work/i586-poky-linux /usr/src/debug

5. On target side, ipaddr is 128.224.163.187,
    run gdbserver to debug "gzip -h"

root@qemux86-64:~# gdbserver localhost:1024 gzip -h
Process gzip created; pid = 530
Listening on port 1024

6. On host side, enter gzip's devshell
$ bitbake -cdevshell gzip

7. On host side, run gdb-cross to remote debug gzip

gzip-1.6# i586-poky-linux-gdb ../build/gzip

8. Use path ${STAGING_DIR_HOST} as the system root for
    the program being debugged. Any absolute shared
    library paths will be prefixed with path;

(gdb) set sysroot /TOPDIR/tmp/sysroots/qemux86


9. Start remote target, set break point at help()

(gdb) target remote 128.224.163.187:1024
(gdb) break gzip.c:325
(gdb) info break
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x0000000000401ec1 in main at 
/usr/src/debug/gzip/1.6-r0/gzip-1.6/gzip.c:325
(gdb) c
Continuing.

Breakpoint 1, main (argc=2, argv=0x7fffffffeca8) at 
/usr/src/debug/gzip/1.6-r0/gzip-1.6/gzip.c:465
465                 help(); do_exit(OK); break;
(gdb) list
460             case 'd':
461                 decompress = 1; break;
462             case 'f':
463                 force++; break;
464             case 'h': case 'H':
465                 help(); do_exit(OK); break;
466             case 'k':
467                 keep = 1; break;
468             case 'l':
469                 list = decompress = to_stdout = 1; break;
(gdb) c
Continuing.
[Inferior 1 (process 1246) exited normally]


10. On target side, get output of "gzip -h"
[snip]
Remote debugging from host 128.224.153.74
Usage: gzip [OPTION]... [FILE]...
Compress or uncompress FILEs (by default, compress FILES in-place).

Mandatory arguments to long options are mandatory for short options too.

   -c, --stdout      write on standard output, keep original files unchanged
   -d, --decompress  decompress
   -f, --force       force overwrite of output file and compress links
   -h, --help        give this help
   -k, --keep        keep (don't delete) input files
   -l, --list        list compressed file contents
   -L, --license     display software license
   -n, --no-name     do not save or restore the original name and time stamp
   -N, --name        save or restore the original name and time stamp
   -q, --quiet       suppress all warnings
   -r, --recursive   operate recursively on directories
   -S, --suffix=SUF  use suffix SUF on compressed files
   -t, --test        test compressed file integrity
   -v, --verbose     verbose mode
   -V, --version     display version number
   -1, --fast        compress faster
   -9, --best        compress better

With no FILE, or when FILE is -, read standard input.

Report bugs to <bug-gzip@gnu.org>.

Child exited with status 0
GDBserver exiting
[snip]

//Hongxu