I am using Linux Kernel Version 2.6.34.6 SMP for powerPC 64 bit. I tried to debug kernel using KGDB and ended up in Kernel panic reboot issue. Here is the list of steps I did. 1) I enabled the following in the config file CONFIG_DEBUG_PAGEALLOC=y CONFIG_DEBUG_KERNEL=y CONFIG_DEBUG_INFO=y CONFIG_KGDB=y CONFIG_FRAME_POINTER=y CONFIG_KGDB_SERIAL_CONSOLE=y Built and loaded the Kernel. 2) My Linux PC is connected terminal server using ttyS0 and I enabled KGDB over serial port by doing "echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc" 3) Trigger KGDB by issuing sysrq-g. echo g > /proc/sysrq-trigger 4) Kernel Panic reboot is seen with the following reboot log sw0:root> echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc kgdb: Registered I/O driver kgdboc. sw0:root> echo g > /proc/sysrq-trigger SysRq : DEBUG Entering KGDB Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x00000000 KGDB: re-enter exception: ALL breakpoints killed Call Trace: STACK MAGIC 0x57ac6e9d [813679c0] [40007fcc] show_stack+0x84/0x24c (unreliable) [81367a20] [4057d9f4] dump_stack+0x2c/0x44 [81367a30] [40098008] kgdb_handle_exception+0x184/0x1b8 [81367a80] [40013320] kgdb_debugger+0x88/0xa0 [81367a90] [4000f5a4] die+0x48/0x28c [81367ac0] [40019460] bad_page_fault+0x90/0xe0 [81367ae0] [400123fc] handle_page_fault+0x7c/0x80 [81367ba0] [407a0000] kmalloc_caches+0xdc0/0x1340 [81367bb0] [402d11ac] uart_poll_get_char+0x58/0x70 [81367bc0] [402daae8] kgdboc_get_char+0x40/0x58 [81367bd0] [40096eac] kgdb_cpu_enter+0x420/0x1320 [81367c60] [40097f08] kgdb_handle_exception+0x84/0x1b8 [81367cb0] [40013250] kgdb_handle_breakpoint+0x4c/0x94 [81367cc0] [40578dbc] program_check_exception+0x5c/0x860 [81367da0] [40012544] ret_from_except_full+0x0/0x4c [81367e60] [40096018] sysrq_handle_gdb+0x94/0xb0 [81367e70] [402c9f28] __handle_sysrq+0xe0/0x1c8 [81367ea0] [402ca06c] write_sysrq_trigger+0x5c/0x80 [81367eb0] [401614a4] proc_reg_write+0x90/0xcc [81367ee0] [4011201c] vfs_write+0xb4/0x1a8 [81367f00] [401122b0] sys_write+0x60/0x144 [81367f40] [40011f4c] ret_from_syscall+0x0/0x3c Kernel panic - not syncing: Recursive entry to debugger Call Trace: STACK MAGIC 0x57ac6e9d Can you help me to understand the root cause of the issue? Let me know how to solve this issue. Thanks Jegan