Commit Graph

27 Commits

Author SHA1 Message Date
Niklas Schnelle
b157f0e97e kgdb: add HAS_IOPORT dependency
In a future patch HAS_IOPORT=n will disable inb()/outb() and friends at
compile time.  We thus need to add HAS_IOPORT as dependency for those
drivers using them.

Link: https://lkml.kernel.org/r/20240403132547.762429-2-schnelle@linux.ibm.com
Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 21:07:05 -07:00
Lukas Bulwahn
5c49b6a4a4 vt: remove superfluous CONFIG_HW_CONSOLE
The config HW_CONSOLE is always identical to the config VT and is not
visible in the kernel's build menuconfig. So, CONFIG_HW_CONSOLE is
redundant.

Replace all references to CONFIG_HW_CONSOLE with CONFIG_VT and remove
CONFIG_HW_CONSOLE.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20240108134102.601-1-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-27 19:03:51 -08:00
Helge Deller
027c3d345e parisc: Convert PDC console to an early console
Rewrite the PDC console to become an early console.
Beside the fact that now boot information is visible until another
(text- or graphics) console takes over, this benefits as well machines
with a yet-unsupported STI console and kgdb.

Signed-off-by: Helge Deller <deller@gmx.de>
2022-10-11 12:01:24 +02:00
Daniel Thompson
f2d10ff4a9 kgdb: Honour the kprobe blocklist when setting breakpoints
Currently kgdb has absolutely no safety rails in place to discourage or
prevent a user from placing a breakpoint in dangerous places such as
the debugger's own trap entry/exit and other places where it is not safe
to take synchronous traps.

Introduce a new config symbol KGDB_HONOUR_BLOCKLIST and modify the
default implementation of kgdb_validate_break_address() so that we use
the kprobe blocklist to prohibit instrumentation of critical functions
if the config symbol is set. The config symbol dependencies are set to
ensure that the blocklist will be enabled by default if we enable KGDB
and are compiling for an architecture where we HAVE_KPROBES.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20200927211531.1380577-2-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-09-28 12:14:08 +01:00
Vincent Chen
8c080d3a97
kgdb: enable arch to support XML packet.
The XML packet could be supported by required architecture if the
architecture defines CONFIG_HAVE_ARCH_KGDB_QXFER_PKT and implement its own
kgdb_arch_handle_qxfer_pkt(). Except for the kgdb_arch_handle_qxfer_pkt(),
the architecture also needs to record the feature supported by gdb stub
into the kgdb_arch_gdb_stub_feature, and these features will be reported
to host gdb when gdb stub receives the qSupported packet.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-09 20:09:28 -07:00
Douglas Anderson
b1a57bbfcc kgdb: Delay "kgdbwait" to dbg_late_init() by default
Using kgdb requires at least some level of architecture-level
initialization.  If nothing else, it relies on the architecture to
pass breakpoints / crashes onto kgdb.

On some architectures this all works super early, specifically it
starts working at some point in time before Linux parses
early_params's.  On other architectures it doesn't.  A survey of a few
platforms:

a) x86: Presumably it all works early since "ekgdboc" is documented to
   work here.
b) arm64: Catching crashes works; with a simple patch breakpoints can
   also be made to work.
c) arm: Nothing in kgdb works until
   paging_init() -> devicemaps_init() -> early_trap_init()

Let's be conservative and, by default, process "kgdbwait" (which tells
the kernel to drop into the debugger ASAP at boot) a bit later at
dbg_late_init() time.  If an architecture has tested it and wants to
re-enable super early debugging, they can select the
ARCH_HAS_EARLY_DEBUG KConfig option.  We'll do this for x86 to start.
It should be noted that dbg_late_init() is still called quite early in
the system.

Note that this patch doesn't affect when kgdb runs its init.  If kgdb
is set to initialize early it will still initialize when parsing
early_param's.  This patch _only_ inhibits the initial breakpoint from
"kgdbwait".  This means:

* Without any extra patches arm64 platforms will at least catch
  crashes after kgdb inits.
* arm platforms will catch crashes (and could handle a hardcoded
  kgdb_breakpoint()) any time after early_trap_init() runs, even
  before dbg_late_init().

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200507130644.v4.4.I3113aea1b08d8ce36dc3720209392ae8b815201b@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-05-18 17:49:27 +01:00
Krzysztof Kozlowski
68d4b3dfca lib/: fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /	/' -i */Kconfig

Link: http://lkml.kernel.org/r/20191120140140.19148-1-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Mauro Carvalho Chehab
08c76a2f43 lib: update location of kgdb documentation
The documentation was moved from DocBook directory.
Update its location.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-16 08:44:22 -03:00
Jiri Slaby
c5d2cac0f1 kgdb: depends on VT
With VT=n, the kernel build fails with:

  drivers/built-in.o: In function `kgdboc_pre_exp_handler':
  kgdboc.c:(.text+0x7b5aa): undefined reference to `fg_console'
  kgdboc.c:(.text+0x7b5ce): undefined reference to `vc_cons'
  kgdboc.c:(.text+0x7b5d5): undefined reference to `vc_cons'

kgdboc.o is built when KGDB_SERIAL_CONSOLE is set.  So make
KGDB_SERIAL_CONSOLE depend on HW_CONSOLE which includes those symbols.

Link: http://lkml.kernel.org/r/1459412955-4696-1-git-send-email-jslaby@suse.cz
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: "Jim Davis" <jim.epost@gmail.com>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00
Daniel Thompson
b8017177cd kdb: Allow access to sensitive commands to be restricted by default
Currently kiosk mode must be explicitly requested by the bootloader or
userspace. It is convenient to be able to change the default value in a
similar manner to CONFIG_MAGIC_SYSRQ_DEFAULT_MASK.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11 09:31:52 -06:00
Masanari Iida
278cee0515 treewide: Fix typo in printk
Correct spelling typo in printk within various drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-06-18 13:48:45 +02:00
Linus Torvalds
3cfb07743a KGDB/KDB fixes and cleanups
Cleanups
    Remove kdb ssb command - there is no in kernel disassembler to support it
    Remove kdb ll command - Always caused a kernel oops and there were no
        bug reports so no one was using this command
    Use kernel ARRAY_SIZE macro instead of array computations
 
  Fixes
    Stop oops in kdb if user executes kdb_defcmd with args
    kdb help command truncated text
    ppc64 support for kgdbts
    Add missing kconfig option from original kdb port for dealing with
       catastrophic kernel crashes such that you can reboot automatically
       on continue from kdb
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJRMhJPAAoJEIciOldedpOj25gP+wZn/u3YxOGkhL3CIBOegEwW
 KFte7FFNeLNzw8tyEzBMVXok85PJ+/lvm+Xi+a4hhtV7/S+WvwGoWeIg0zCDtrAu
 im4m2X1u00Egcztcr4tCk8Lwc6vNm5KZsBsUsbKKi0K8twaWifkxLMEWeq+3WLzh
 +1d4TDkziwdZfcLpUHvohmCsCyg1EdjUxTYnWpSJvLrq5lhNvTQBowHWZH06GBcI
 MmhC+aHp3myk2/Vwd1AuDq+jIRbH3ORV50wfRONBR7OJ58sOoD9nV8Mr+fy8QLRN
 BPv8WxeRSm7X/Hl6nPm9PX7oNQSg+Ba1+5helIIJMdGGWhJbl9AZslFEU40Zn3yS
 V7FmS3mwRSA8NCgfZ+CO6311tirSCvtf34+5ttXEntyK1ujaplSPffBP4Ya26y6q
 TB2wLr91+3L0LhzrVRj20P13qexsWUW4t9inLzqtDApD3Zljl9Kuwd0febCiLg0r
 mgGkpZjK0VI7S7RfkxpmEyU4bFP2lCTzBOKAKOfIV6O88bfqFdv5QCTHODJArf22
 ugDGPX3tw++Lyc9otGxyPbxmc7npYGqTD1UEM8xK/7sEBiWJm71jjwHN1bwRwB3o
 EC5bcZ6TJgDJnnvYGBTQec74PnUiCu/UnQVFFabzhowQCJTIWSJkPxjnI2BKK1V5
 3exPqogclusAhhwopOtG
 =Hwbq
 -----END PGP SIGNATURE-----

Merge tag 'for_linux-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb

Pull KGDB/KDB fixes and cleanups from Jason Wessel:
 "For a change we removed more code than we added.  If people aren't
  using it we shouldn't be carrying it.  :-)

  Cleanups:
   - Remove kdb ssb command - there is no in kernel disassembler to
     support it

   - Remove kdb ll command - Always caused a kernel oops and there were
     no bug reports so no one was using this command

   - Use kernel ARRAY_SIZE macro instead of array computations

  Fixes:
   - Stop oops in kdb if user executes kdb_defcmd with args

   - kdb help command truncated text

   - ppc64 support for kgdbts

   - Add missing kconfig option from original kdb port for dealing with
     catastrophic kernel crashes such that you can reboot automatically
     on continue from kdb"

* tag 'for_linux-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
  kdb: Remove unhandled ssb command
  kdb: Prevent kernel oops with kdb_defcmd
  kdb: Remove the ll command
  kdb_main: fix help print
  kdb: Fix overlap in buffers with strcpy
  Fixed dead ifdef block by adding missing Kconfig option.
  kdb: Setup basic kdb state before invoking commands via kgdb
  kdb: use ARRAY_SIZE where possible
  kgdb/kgdbts: support ppc64
  kdb: A fix for kdb command table expansion
2013-03-02 08:31:39 -08:00
Robert Obermeier
3b0eb71ec9 Fixed dead ifdef block by adding missing Kconfig option.
Added missing Kconfig option KDB_CONTINUE_CATASTROPHIC which lead to a dead
ifdef block in kernel/debug/kdb/kdb_main.c:73-75.

The code using KDB_CONTINUE_CATASTROPHIC was originally introduced in
commit '5d5314d6795f3c1c0f415348ff8c51f7de042b77' by Jason Wessel.
This patchset ("kdb: core for kgdb back end (1 of 2)")
added platform independent part of kdb to the linux kernel.

The Kernel option however, even though it had the same options and
behaviour on all supported architectures, was part of the x86 and
ia64 patchset of KDB and therefore not pulled into the mainline kernel tree.

I actually took the originally written Kconfig by
Keith Owens <kaos@sgi.com> (2003-06-20 according to KDB changelog)
and changed it to reflect the correct behaviour,
as the KDUMP patchset is not part of the kernel and the expected
functionality is missing from it.

Signed-off-by: Robert Obermeier <obbi89@googlemail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02 08:52:18 -06:00
Linus Torvalds
21eaab6d19 tty/serial patches for 3.9-rc1
Here's the big tty/serial driver patches for 3.9-rc1.
 
 More tty port rework and fixes from Jiri here, as well as lots of
 individual serial driver updates and fixes.
 
 All of these have been in the linux-next tree for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iEYEABECAAYFAlEmZYQACgkQMUfUDdst+ylJDgCg0B0nMevUUdM4hLvxunbbiyXM
 HUEAoIOedqriNNPvX4Bwy0hjeOEaWx0g
 =vi6x
 -----END PGP SIGNATURE-----

Merge tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial patches from Greg Kroah-Hartman:
 "Here's the big tty/serial driver patches for 3.9-rc1.

  More tty port rework and fixes from Jiri here, as well as lots of
  individual serial driver updates and fixes.

  All of these have been in the linux-next tree for a while."

* tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: mxser: improve error handling in mxser_probe() and mxser_module_init()
  serial: imx: fix uninitialized variable warning
  serial: tegra: assume CONFIG_OF
  TTY: do not update atime/mtime on read/write
  lguest: select CONFIG_TTY to build properly.
  ARM defconfigs: add missing inclusions of linux/platform_device.h
  fb/exynos: include platform_device.h
  ARM: sa1100/assabet: include platform_device.h directly
  serial: imx: Fix recursive locking bug
  pps: Fix build breakage from decoupling pps from tty
  tty: Remove ancient hardpps()
  pps: Additional cleanups in uart_handle_dcd_change
  pps: Move timestamp read into PPS code proper
  pps: Don't crash the machine when exiting will do
  pps: Fix a use-after free bug when unregistering a source.
  pps: Use pps_lookup_dev to reduce ldisc coupling
  pps: Add pps_lookup_dev() function
  tty: serial: uartlite: Support uartlite on big and little endian systems
  tty: serial: uartlite: Fix sparse and checkpatch warnings
  serial/arc-uart: Miscll DT related updates (Grant's review comments)
  ...

Fix up trivial conflicts, mostly just due to the TTY config option
clashing with the EXPERIMENTAL removal.
2013-02-21 13:41:04 -08:00
Joe Millenbach
4f73bc4dd3 tty: Added a CONFIG_TTY option to allow removal of TTY
The option allows you to remove TTY and compile without errors. This
saves space on systems that won't support TTY interfaces anyway.
bloat-o-meter output is below.

The bulk of this patch consists of Kconfig changes adding "depends on
TTY" to various serial devices and similar drivers that require the TTY
layer.  Ideally, these dependencies would occur on a common intermediate
symbol such as SERIO, but most drivers "select SERIO" rather than
"depends on SERIO", and "select" does not respect dependencies.

bloat-o-meter output comparing our previous minimal to new minimal by
removing TTY.  The list is filtered to not show removed entries with awk
'$3 != "-"' as the list was very long.

add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
function                                     old     new   delta
chr_dev_init                                 166     170      +4
allow_signal                                  80      82      +2
static.__warned                              143     142      -1
disallow_signal                               63      62      -1
__set_special_pids                            95      94      -1
unregister_console                           126     121      -5
start_kernel                                 546     541      -5
register_console                             593     588      -5
copy_from_user                                45      40      -5
sys_setsid                                   128     120      -8
sys_vhangup                                   32      19     -13
do_exit                                     1543    1526     -17
bitmap_zero                                   60      40     -20
arch_local_irq_save                          137     117     -20
release_task                                 674     652     -22
static.spin_unlock_irqrestore                308     260     -48

Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-18 16:15:27 -08:00
Kees Cook
525c1f9204 lib: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
CC: James Morris <james.l.morris@oracle.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Akinobu Mita <akinobu.mita@gmail.com>
CC: Ingo Molnar <mingo@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 12:11:27 -08:00
Jason Wessel
5dd11d5d47 mips,kgdb: kdb low level trap catch and stack trace
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" do_trap_or_bp() handler.

Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.

Also added was a die notification for oops such that kdb can catch an
oops for analysis.

There appeared to be no obvious way to pass the struct pt_regs from
the original exception back to the stack back tracer, so a special
case was added to show_stack() for when kdb is active because you
generally desire to generally look at the back trace of the original
exception.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
2010-05-20 21:04:26 -05:00
Jason Wessel
f503b5ae53 x86,kgdb: Add low level debug hook
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a triple fault is
to have a low level "first opportunity handler" in the int3 exception
handler.

Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.

CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: H. Peter Anvin <hpa@zytor.com>
CC: x86@kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20 21:04:25 -05:00
Jason Wessel
ada64e4c98 kgdboc,keyboard: Keyboard driver for kdb with kgdb
This patch adds in the kdb PS/2 keyboard driver.  This was mostly a
direct port from the original kdb where I cleaned up the code against
checkpatch.pl and added the glue to stitch it into kgdb.

This patch also enables early kdb debug via kgdbwait and the keyboard.

All the access to configure kdb using either a serial console or the
keyboard is done via kgdboc.

If you want to use only the keyboard and want to break in early you
would add to your kernel command arguments:

    kgdboc=kbd kgdbwait

If you wanted serial and or the keyboard access you could use:

    kgdboc=kbd,ttyS0

You can also configure kgdboc as a kernel module or at run time with
the sysfs where you can activate and deactivate kgdb.

Turn it on:
    echo kbd,ttyS0 > /sys/module/kgdboc/parameters/kgdboc

Turn it off:
    echo "" > /sys/module/kgdboc/parameters/kgdboc

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2010-05-20 21:04:24 -05:00
Jason Wessel
dcc7871128 kgdb: core changes to support kdb
These are the minimum changes to the kgdb core in order to enable an
API to connect a new front end (kdb) to the debug core.

This patch introduces the dbg_kdb_mode variable controls where the
user level I/O is routed.  It will be routed to the gdbstub (kgdb) or
to the kdb front end which is a simple shell available over the kgdboc
connection.

You can switch back and forth between kdb or the gdb stub mode of
operation dynamically.  From gdb stub mode you can blindly type
"$3#33", or from the kdb mode you can enter "kgdb" to switch to the
gdb stub.

The logic in the debug core depends on kdb to look for the typical gdb
connection sequences and return immediately with KGDB_PASS_EVENT if a
gdb serial command sequence is detected.  That should allow a
reasonably seamless transition between kdb -> gdb without leaving the
kernel exception state.  The two gdb serial queries that kdb is
responsible for detecting are the "?" and "qSupported" packets.

CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Martin Hicks <mort@sgi.com>
2010-05-20 21:04:21 -05:00
Jason Wessel
5f5ddfb360 kgdb: remove the requirement for CONFIG_FRAME_POINTER
There is no technical reason that the kgdb core requires frame
pointers.  It is up to the end user of KGDB to decide if they need
them or not.

[ anemo@mba.ocn.ne.jp: removed frame pointers on mips ]

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2008-08-01 08:39:34 -05:00
Jason Wessel
68afab1cb3 kgdb: remove unused HAVE_ARCH_KGDB_SHADOW_INFO config variable
Remove HAVE_ARCH_KGDB_SHADOW_INFO because it does not
exist anywhere in the kernel mainline sources

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2008-07-23 11:30:15 -05:00
Jan Engelhardt
e024cbd257 kgdb: kconfig fix xconfig/menuconfig element
Kconfig.kgdb: fix menuconfig element

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2008-05-05 07:13:21 -05:00
Jason Wessel
974460c5bf kgdb: allow static kgdbts boot configuration
This patch adds in the ability to compile the kgdb internal test
string into the kernel so as to run the tests at boot without changing
the kernel boot arguments.  This patch also changes all the error
paths to invoke WARN_ON(1) which will emit the line number of the file
and dump the kernel stack when an error occurs.

You can disable the tests in a kernel that is built this way
using "kgdbts="

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 20:05:43 +02:00
Jason Wessel
e8d31c204e kgdb: add kgdb internal test suite
This patch adds regression tests for testing the kgdb core and arch
specific implementation.

The kgdb test suite is designed to be built into the kernel and not as
a module because it uses a number of low level kernel and kgdb
primitives which should not be exported externally.

The kgdb test suite is designed as a KGDB I/O module which
simulates the communications that a debugger would have with kgdb.
The tests are broken up in to a line by line and referenced here as
a "get" which is kgdb requesting input and "put" which is kgdb
sending a response.

The kgdb suite can be invoked from the kernel command line
arguments system or executed dynamically at run time.  The test
suite uses the variable "kgdbts" to obtain the information about
which tests to run and to configure the verbosity level.  The
following are the various characters you can use with the kgdbts=
line:

When using the "kgdbts=" you only choose one of the following core
test types:
A = Run all the core tests silently
V1 = Run all the core tests with minimal output
V2 = Run all the core tests in debug mode

You can also specify optional tests:
N## = Go to sleep with interrupts of for ## seconds
      to test the HW NMI watchdog
F## = Break at do_fork for ## iterations
S## = Break at sys_open for ## iterations

NOTE: that the do_fork and sys_open tests are mutually exclusive.

To invoke the kgdb test suite from boot you use a kernel start
argument as follows:
	kgdbts=V1 kgdbwait
Or if you wanted to perform the NMI test for 6 seconds and do_fork
test for 100 forks, you could use:
	kgdbts=V1N6F100 kgdbwait

The test suite can also be invoked at run time with:
echo kgdbts=V1N6F100 > /sys/module/kgdbts/parameters/kgdbts
Or as another example:
echo kgdbts=V2 > /sys/module/kgdbts/parameters/kgdbts

When developing a new kgdb arch specific implementation or
using these tests for the purpose of regression testing,
several invocations are required.

1) Boot with the test suite enabled by using the kernel arguments
      "kgdbts=V1F100 kgdbwait"
   ## If kgdb arch specific implementation has NMI use
      "kgdbts=V1N6F100

2) After the system boot run the basic test.
echo kgdbts=V1 > /sys/module/kgdbts/parameters/kgdbts

3) Run the concurrency tests.  It is best to use n+1
   while loops where n is the number of cpus you have
   in your system.  The example below uses only two
   loops.

## This tests break points on sys_open
while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
echo kgdbts=V1S10000 > /sys/module/kgdbts/parameters/kgdbts
fg # and hit control-c
fg # and hit control-c
## This tests break points on do_fork
while [ 1 ] ; do date > /dev/null ; done &
while [ 1 ] ; do date > /dev/null ; done &
echo kgdbts=V1F1000 > /sys/module/kgdbts/parameters/kgdbts
fg # and hit control-c

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 20:05:42 +02:00
Jason Wessel
dc7d552705 kgdb: core
kgdb core code. Handles the protocol and the arch details.

[ mingo@elte.hu: heavily modified, simplified and cleaned up. ]
[ xemul@openvz.org: use find_task_by_pid_ns ]

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 20:05:37 +02:00