lib/Kconfig.kgdb

   1 # SPDX-License-Identifier: GPL-2.0-only
   2
   3 config HAVE_ARCH_KGDB
   4         bool
   5
   6 menuconfig KGDB
   7         bool "KGDB: kernel debugger"
   8         depends on HAVE_ARCH_KGDB
   9         depends on DEBUG_KERNEL
  10         help
  11           If you say Y here, it will be possible to remotely debug the
  12           kernel using gdb.  It is recommended but not required, that
  13           you also turn on the kernel config option
  14           CONFIG_FRAME_POINTER to aid in producing more reliable stack
  15           backtraces in the external debugger.  Documentation of
  16           kernel debugger is available at http://kgdb.sourceforge.net
  17           as well as in Documentation/dev-tools/kgdb.rst.  If
  18           unsure, say N.
  19
  20 if KGDB
  21
  22 config KGDB_SERIAL_CONSOLE
  23         tristate "KGDB: use kgdb over the serial console"
  24         select CONSOLE_POLL
  25         select MAGIC_SYSRQ
  26         depends on TTY && HW_CONSOLE
  27         default y
  28         help
  29           Share a serial console with kgdb. Sysrq-g must be used
  30           to break in initially.
  31
  32 config KGDB_TESTS
  33         bool "KGDB: internal test suite"
  34         default n
  35         help
  36           This is a kgdb I/O module specifically designed to test
  37           kgdb's internal functions.  This kgdb I/O module is
  38           intended to for the development of new kgdb stubs
  39           as well as regression testing the kgdb internals.
  40           See the drivers/misc/kgdbts.c for the details about
  41           the tests.  The most basic of this I/O module is to boot
  42           a kernel boot arguments "kgdbwait kgdbts=V1F100"
  43
  44 config KGDB_TESTS_ON_BOOT
  45         bool "KGDB: Run tests on boot"
  46         depends on KGDB_TESTS
  47         default n
  48         help
  49           Run the kgdb tests on boot up automatically without the need
  50           to pass in a kernel parameter
  51
  52 config KGDB_TESTS_BOOT_STRING
  53         string "KGDB: which internal kgdb tests to run"
  54         depends on KGDB_TESTS_ON_BOOT
  55         default "V1F100"
  56         help
  57           This is the command string to send the kgdb test suite on
  58           boot.  See the drivers/misc/kgdbts.c for detailed
  59           information about other strings you could use beyond the
  60           default of V1F100.
  61
  62 config KGDB_LOW_LEVEL_TRAP
  63        bool "KGDB: Allow debugging with traps in notifiers"
  64        depends on X86 || MIPS
  65        default n
  66        help
  67          This will add an extra call back to kgdb for the breakpoint
  68          exception handler which will allow kgdb to step through a
  69          notify handler.
  70
  71 config KGDB_KDB
  72         bool "KGDB_KDB: include kdb frontend for kgdb"
  73         default n
  74         help
  75           KDB frontend for kernel
  76
  77 config KDB_DEFAULT_ENABLE
  78         hex "KDB: Select kdb command functions to be enabled by default"
  79         depends on KGDB_KDB
  80         default 0x1
  81         help
  82           Specifiers which kdb commands are enabled by default. This may
  83           be set to 1 or 0 to enable all commands or disable almost all
  84           commands.
  85
  86           Alternatively the following bitmask applies:
  87
  88             0x0002 - allow arbitrary reads from memory and symbol lookup
  89             0x0004 - allow arbitrary writes to memory
  90             0x0008 - allow current register state to be inspected
  91             0x0010 - allow current register state to be modified
  92             0x0020 - allow passive inspection (backtrace, process list, lsmod)
  93             0x0040 - allow flow control management (breakpoint, single step)
  94             0x0080 - enable signalling of processes
  95             0x0100 - allow machine to be rebooted
  96
  97           The config option merely sets the default at boot time. Both
  98           issuing 'echo X > /sys/module/kdb/parameters/cmd_enable' or
  99           setting with kdb.cmd_enable=X kernel command line option will
 100           override the default settings.
 101
 102 config KDB_KEYBOARD
 103         bool "KGDB_KDB: keyboard as input device"
 104         depends on VT && KGDB_KDB
 105         default n
 106         help
 107           KDB can use a PS/2 type keyboard for an input device
 108
 109 config KDB_CONTINUE_CATASTROPHIC
 110         int "KDB: continue after catastrophic errors"
 111         depends on KGDB_KDB
 112         default "0"
 113         help
 114           This integer controls the behaviour of kdb when the kernel gets a
 115           catastrophic error, i.e. for a panic or oops.
 116           When KDB is active and a catastrophic error occurs, nothing extra
 117           will happen until you type 'go'.
 118           CONFIG_KDB_CONTINUE_CATASTROPHIC == 0 (default). The first time
 119           you type 'go', you will be warned by kdb. The secend time you type
 120           'go', KDB tries to continue. No guarantees that the
 121           kernel is still usable in this situation.
 122           CONFIG_KDB_CONTINUE_CATASTROPHIC == 1. KDB tries to continue.
 123           No guarantees that the kernel is still usable in this situation.
 124           CONFIG_KDB_CONTINUE_CATASTROPHIC == 2. KDB forces a reboot.
 125           If you are not sure, say 0.
 126
 127 endif # KGDB