Linux 2.6.10 kgdb
 

Hi,

I compiled the linux2.6.10 kernel in the development machine as per kgdb websites suggection and then transferred the image to the test machine. Now when I start gdb (in the dev machine) after booting the test host, I get the following error messages,

This GDB was configured as "i386-redhat-linux-gnu"...0xc014258b in ?? ()

(gdb) cont
Continuing.
Waiting for connection from remote gdb...
audit(1123541664.693:0): initialized
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[New Thread 1]

Program received signal SIGTRAP, Trace/breakpoint trap.
[Switching to Thread 1]
breakpoint () at kernel/kgdb.c:1453
1453 atomic_set(&kgdb_setting_breakpoint, 0);
(gdb) bt
#0 breakpoint () at kernel/kgdb.c:1453
#1 0xc0142525 in kgdb_panic_notify (self=0x1, cmd=0, ptr=0xc0404c80)
at kernel/kgdb.c:1310
#2 0xc01300d8 in notifier_call_chain (n=0x1, val=0, v=0xc0404c80)
at kernel/sys.c:172
#3 0xc0122a1a in panic (fmt=0xc0319668 "VFS: Unable to mount root fs on %s")
at kernel/panic.c:78
#4 0xc03c326d in mount_block_root (name=0xc0319e75 "/dev/root", flags=32769)
at init/do_mounts.c:306
#5 0xc03c349a in prepare_namespace () at init/do_mounts.c:407
#6 0xc01005e5 in init (unused=0x1) at init/main.c:729
#7 0xc01022b5 in kernel_thread_helper () at arch/i386/kernel/process.c:238

Any ideas?

Problem why you are getting this message is you while booting up the board with kgdb linux kernel the options you gave in the boot command is wrong.

CFE> boot -z -elf devolpment_machine_ip:vmlinux 'root=/dev/nfs nfsroot=nfsroot_direcotry_path rw ip=target_machine_ipaddress'.

try this command this will solve your problem.

I have one query. Are you using null modem cable for kernel debugging . If so can you please tell me the configuration of it.

Cheers
-Murali