This is a cut and paste from the manual. http://kernel.org/pub/linux/kernel/people/jwessel/kgdb/
If something is not clear, please help clear up the documentation. ------ NOTE: Kgdboc does not support interrupting the target via the gdb remote protocol. You must manually send a sysrq-g unless you have a proxy that splits console output to a terminal problem and has a separate port for the debugger to connect to that sends the sysrq-g for you. When using kgdboc with no debugger proxy, you can end up connecting the debugger for one of two entry points. If an exception occurs after you have loaded kgdboc a message should print on the console stating it is waiting for the debugger. In case you disconnect your terminal program and then connect the debugger in its place. If you want to interrupt the target system and forcibly enter a debug session you have to issue a Sysrq sequence and then type the letter |g|. Then you disconnect the terminal session and connect gdb. Your options if you don't like this are to hack gdb to send the sysrq-g for you as well as on the initial connect, or to use a debugger proxy that allows an unmodified gdb to do the debugging. ------ Rieker Flaik wrote: > Hi, > > Thanks for this nice peace of code. > > I just tried the kgdb_light from 2.6.26.1 and activated it by a lilo > append "kgdbwait kgdboc=ttyS0,115200". > Without any sysreq-g that I also don't understand it worked just by > starting "gdb ./vmlinux" on the other machine connected by a > rs232-nullmodem-cable. Then I did: > "set remotebaud 115200" > "target remote /dev/ttyS2" > > and voila, I'm in. > > But now, I'm interested in debugging the kernel at a later time out of > a running system. In the LinSysSoft-Docu I found a chapter about > "Controlling the execution of a kernel" by just hitting "Ctrl+C on the > gdb-terminal". But this doesn't work. I can do a "continue" in gdb, but > a Ctrl+C doesn't stop and get's me back to single-stepping. > > How is this done in kgdb_light? > > regards > > > ------------------------------------------------------------------------- > This SF.Net email is sponsored by the Moblin Your Move Developer's challenge > Build the coolest Linux based applications with Moblin SDK & win great prizes > Grand prize is a trip for two to an Open Source event anywhere in the world > http://moblin-contest.org/redirect.php?banner_id=100&url=/ > _______________________________________________ > Kgdb-bugreport mailing list > Kgdb-bugreport@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport > ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Kgdb-bugreport mailing list Kgdb-bugreport@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport
