From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Mathur, Shobhit" Subject: linux-source debugging with kgdb-patch Date: Thu, 17 Apr 2003 20:46:24 +0530 Sender: linux-serial-owner@vger.kernel.org Message-ID: <3E9EC548.117005DD@adaptec.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: Content-Type: text/plain; charset="us-ascii" To: linux-c-programming@vger.kernel.org, linux-serial@vger.kernel.org, linux-newbie@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Hello, BACKGROUND: I was keen to see kgdb running for purely academic reasons. Thus, I made a setup of 2 machines for source-level debugging of the linux-kernel. The procedure mentioned on the web-site [ kgdb.sourceforge.net] has been adhered to. I was able to successfully configure the setup. Also, I decided to use "ddd" front-end on gdb [local m/c] for debugging the kgdb-patched kernel on the remote machine, which is the usual setup for such debugging-efforts. The m/c to be debugged stops with the message "Waiting for connection from remote gdb..." until the "target remote" command is run from the "gdb" prompt of "ddd", upon which the m/c to be debugged continues it's bootup till it shows the command-prompt. PROBLEM: I was interested in setting a break-point in start_kernel thru' "ddd" such that the boot-up of the m/c to be debugged could be analysed step-by-step remotely. Though, I am able to set the breakpoint in start_kernel(), the commands "run" or "continue" on the "gdb" prompt, only throw up the following errors : (gdb) info break Num Type Disp Enb Address What 7 breakpoint keep y 0xc027e7f0 in start_kernel at init/main.c:614 (gdb) run warning: shared library handler failed to enable breakpoint warning: Cannot insert breakpoint 7: Cannot access memory at address 0xc027e7f0 QUESTION: I very strongly suspect that this exercise follows a particular sequence of steps to get it right. Either I am missing some step or I am not following the "order". In either case, I would be glad to receive some help/comments on my academic endeavour to be able to remotely debug the kernel. - Kindly let me know a solution - TIA - Shobhit Mathur