I'm having a hard time building a kernel with kdbg support. In ltib i was able to configure the kernel and everything seemed to build. I'm using a nitrogen6x board though, I'm not sure how much stuff this will break.
Starting up with uboot I added kgdb args
setenv bootargs kgdboc=ttymxc0,115200 kgdbwait ip=dhcp
it doesn't stop, I aslo don't believe its loading the correct config to build, my kernel with debugging symbols is about the same size as my kernel without....
I tried to build directly with the sources, but when I do that, after configuring the kernel, it automatically restarts the config process... from the beginning without a menu.
My second problem is I have two serial ports, and my device is deciding to use both during startup, At some point it switches console output to the second serial port.
Kevin, thanks for your post. I too have connected to i.MX6Q with kgdb using a kernel command line similar to yours. As far as I can tell, there's no way to attach kgdb to the board except for kgdbwait, as drivers/tty/sysrq.c shows no implementation of sysrq-g magic key. I'm wondering how you proceed once you connect the server at the kgdbwait prompt. | Once the gdbserver is connected over the console, what do you do next? |
Like you apparently, I can attach with kgdbwait using the console:
$ arm-none-linux-gnueabi-gdb ./vmlinux
GNU gdb (Sourcery CodeBench 2011.03-119) 7.2.50.20100908-cvs
This GDB was configured as "--host=i686-pc-linux-gnu --target=arm-none-linux-gnueabi".
Reading symbols from /home/achaiken/gitsrc/linux-kernel/vmlinux...done.
(gdb) connect
kgdb_breakpoint () at kernel/debug/debug_core.c:986
986 | arch_kgdb_breakpoint(); |
Breakpoint 1 at 0x80488d00: file kernel/panic.c, line 87.
Breakpoint 2 at 0x8010aa0c: file fs/sync.c, line 100.
(gdb)) i b
Num | Type | Disp Enb Address | What |
1 | breakpoint | keep y 0x80488d00 in panic at kernel/panic.c:87 |
2 | breakpoint | keep y 0x8010aa0c in sys_sync at fs/sync.c:100 |
Unfortunately, when I type "continue" or even "next" or "step" at the gdb prompt, I never see the system come up, as determined by ping or ssh. | (If I don't connect with kgdb, I can easily ping or ssh to the fully booted host.) | I used kernel config similar to yours, and clearly the fact that I can connect in the first place shows that most of the configuration is right. |
Thanks for any suggestions,
Alison Chaiken
ah figured out one of my problems
I kept running menumake without defining the ARCH or CROSS_COMPILE before hand, so I was configuring it for a different build
SUCCESS!