% gdb obj/linux     
GNU gdb Red Hat Linux (6.3.0.0-1.122rh)
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This GDB was configured as "i386-redhat-linux-gnu"...Using host libthread_db library "/lib/libthread_db.so.1".

(gdb) b start_kernel
Breakpoint 1 at 0x80493c3: file /home/jdike/linux/2.6/test/linux-2.6.17/init/main.c, line 461.
(gdb) r
Starting program: /home/jdike/linux/2.6/test/linux-2.6.17/obj/linux 
Reading symbols from shared object read from target memory...done.
Loaded system supplied DSO at 0x615000
Detaching after fork from child process 24108.
Checking that ptrace can change system call numbers...OK
Detaching after fork from child process 24109.
Checking syscall emulation patch for ptrace...OK
Detaching after fork from child process 24110.
Checking advanced syscall emulation patch for ptrace...OK
Checking for tmpfs mount on /dev/shm...OK
Checking PROT_EXEC mmap in /dev/shm/...OK
Checking for the skas3 patch in the host:
  - /proc/mm...not found
Detaching after fork from child process 24111.
  - PTRACE_FAULTINFO...not found
Detaching after fork from child process 24112.
  - PTRACE_LDT...not found
UML running in SKAS0 mode
Adding 25427968 bytes to physical memory to account for exec-shield gap

Breakpoint 1, start_kernel ()
    at /home/jdike/linux/2.6/test/linux-2.6.17/init/main.c:461
461             smp_setup_processor_id();
(gdb) n
469             local_irq_disable();
(gdb)