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    Subject[GIT PULL] kdb / kms / early debug (1 of 2)
    Linus please pull the kdb-merge tree which merges the kdb front end
    into the kernel debug core for 7 architectures.

    git:// kdb-merge

    --- Notes for Linus ---

    Because I touched numerous files outside the kernel debugger I tried
    to get sign off from other maintainers. I received acks and review
    comments for everything but the changes to drivers/input/input.c and
    arch/x86/kernel/traps.c changes in which case I received no response
    at all. In both cases the code is #ifdef'ed such that if you do not
    use a kernel debugger, there is no impact.

    I split the kdb and early debug functionality into 2 trees. If you
    are ok with both trees, you can just pull:

    git:// for_linus

    --- End Notes for Linus ---

    Thank you very much to everyone who provided feedback on the prior
    patch sets.

    Originally this was 3 separate patch sets.

    At the present time the atomic kernel mode setting patch set is in
    review by the drm maintainers and may or make not make the merge

    The history of the combined 3 sets of patches follows.

    The kdb / kgdb functionality is considered stable. The patch set has
    been in linux-next for several months, following the completion of the
    prototype phase which consisted of porting the original SGI maintained
    kdb v4.4 into the kernel debug core and polling I/O hooks. There are
    several people in the community actively making use of the patches.

    You can preview the documentation at:

    Differences in the final patch set vs v3:

    * All controversial patches were dropped
    o The kms series was dropped entirely
    o Modifications to panic.c were dropped
    * All the lockless changes to si_meminfo and swap info were dropped
    * The ppc debug handler was made permanent instead of an #ifdef
    * Acks added for blackfin, mips, printk.c, and dbgp modifications

    Differences in the V3 patch set:

    * The ARM hooks were dropped and implemented another way by RMK
    * X86 hw breakpoint regression patches were merged in 2.6.33-rc7
    * All the NR_CPUS arrays were factored out of the kdb shell
    * The kdb init was divided into an early and late section
    to allow extended commands definitions to use kernel memory
    * The KMS debugger API function names were updated for consistency
    * Several minor bugs fixed in the kdb shell with the pager
    * The early debug series was added to kgdb-next
    * Allows early hardware breakpoints and trap on X86
    * Allows kgdb and kdb over the EHCI USB Debug Port
    * Allows kdb debugging in conjunction with earlyprintk=vga

    Differences in the V2 patch set:

    * All the code is now in linux-next via kgdb-next
    * 6 different build breakages were repaired around different .config
    options not compiling
    * kms / kdb / kgdb was built tested as kernel modules
    * The kdb core was split into 2 patches, 1 for the core, and one for all
    the files touched outside the kdb core
    * kdb_seq_printf added to eliminate the duplicate meminfo commands in procfs
    * kdb breakpoint code refactored to remove unused globals and struct members
    * Fixed the possibility to loop infinitely in the kdb md command
    * Cleaned up the kdb kernel/modules.c patch
    * Removed the unused kdb report helper function in kernel/sched.c
    * HW instruction and data access breakpoints implementation completed
    * The kdb keyboard code no longer modifies include/linux/keyboard.h
    * The kernel_probe_read and kernel_probe_write were cleaned up for blackfin
    * The blackfin arch specific kgdb implementation was cleaned up and merged
    * The debug core now turns off tracing while the kernel debugger is active
    * New in the series is a command for kdb called ftdump, which allows
    dumping the ftrace buffer
    * kdb will automatically set the correct number of rows on the display
    via the information from the vt_console when using kms
    * There is preliminary documentation for kdb and kms
    * The drm hacks patch is still a hack, but cleaned up and using macros

    The acks were added for the blackfin, sparc and sh arch specific code by the
    respective maintainers.

    Differences in the V1 patch set vs the RFC:

    Back in May 2009 an initial kdb prototype was posted to lkml as an RFC
    to see if there was sufficient interest to merge kdb and kgdb together.

    There was enough interest to continue on with the project, and it is
    now in a state where further work can occur to review, and hopefully
    merge the code into a future kernel.

    If this is the first time you have heard about kgdb or kdb, you might
    consider taking a look at the presentation slides from LPC 2009.

    The code included in this series does not include any of the USB code
    referenced in the presentation.

    Several changes have occurred since the original prototype was posted.
    All of the architectures using the kgdb core today have had the
    functions implemented to make use of the kdb shell. This list
    includes x86, arm, ppc, mips, sh, sparc, and blackfin. The proposed
    atomic kernel modesetting project now has an initial implementation
    for the intel i915 driver, and it should be possible to add atomic
    mode setting hooks for any other video driver which makes use of
    builtin kernel mode setting. All the dead code and functions that
    were not previously implemented in the RFC have been removed or

    The directory of the kernel debugger changed as well. All the kernel
    debugger pieces, the debug core, gdbstub and kdb now live under

    While the patch set may be slightly large, it is broken down into
    logical, incremental functionality. Only the first 12 patches are
    needed to see kdb in action on a serial port which has a kgdboc driver
    for example.

    It is important to understand that this work was directly derived from
    the original kdb, and the intent is to deprecate the out of tree kdb
    and move all its functionality to this code base. This version of kdb
    is completely wired into the debug core and the kgdboc polled I/O
    model using the same API used by the gdbstub (which people call kgdb).

    The kdb front end in this patch series works a little differently than
    if you were to take the original kdb patch set from:

    In the kernel .config you should enable the following options:


    To use kdb with a serial port you would use the kgdb/kgdboc way of
    doing things. You would used a kernel command line with:

    console=ttyS0,115200 kgdboc=ttyS0 kgdbwait

    That will get you access to kdb just after the console has been
    registered. If you want to use the keyboard, you could use the
    following (NOTE it is kbd and not kdb, kbd is short for keyboard):

    console=tty0 kgdboc=kbd kgdbwait

    You can also use the keyboard and or serial console:

    console=ttyS0,115200 console=tty0 kgdboc=kbd,ttyS0

    In terms of breaking into the debugger after the system is up, you
    must use the sysrq-g sequence. That means you could run:
    echo g > /proc/sysrq-trigger

    Or you can use the SysRq key on your key board. On a typical laptop
    you might have to do the following:

    press and hold ALT -- You will be holding this the whole time
    press and hold FN
    press and release the key with the SysRq label
    release FN
    press and release g
    release ALT

    Once you are in kdb you can run help to see a limited list of

    You can also still connect gdb or re-enter kdb without leaving the
    exception state, if you are using a serial port. To get out of kgdb
    mode you can type "$3#33", or to get into kgdb mode from kdb, you can
    type "kgdb".

    From gdb you can issue commands to the kdb front end, via gdb's
    monitor command. For instance you could issue "monitor lsmod".
    Allowing the gdb monitor extension was certainly another motivation
    behind the prototype.

    Included among the kdb patches are some kgdb specific fixes for the
    next kernel merge window, and if kdb were to not make the cut, these
    patches will be split out of the series. Anything too ugly for a
    possible merge is also a candidate to get removed from the series.


    The following changes since commit baac35c4155a8aa826c70acee6553368ca5243a2:
    Xiaotian Feng (1):
    security: fix error return path in ima_inode_alloc

    are available in the git repository at:

    git:// kdb-merge

    Jason Wessel (28):
    Move kernel/kgdb.c to kernel/debug/debug_core.c
    Separate the gdbstub from the debug core
    kgdb: eliminate kgdb_wait(), all cpus enter the same way
    kgdb,sparc: Add in kgdb_arch_set_pc for sparc
    kgdb,sh: update superh kgdb exception handling
    kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin
    kdb: core for kgdb back end (1 of 2)
    kdb: core for kgdb back end (2 of 2)
    kgdb: core changes to support kdb
    kgdb,8250,pl011: Return immediately from console poll
    sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code
    sparc,sunzilog: Add console polling support for sunzilog serial driver
    kgdb: gdb "monitor" -> kdb passthrough
    kgdboc,keyboard: Keyboard driver for kdb with kgdb
    kgdb,docs: Update the kgdb docs to include kdb
    kgdb: remove post_primary_code references
    x86,kgdb: Add low level debug hook
    powerpc,kgdb: Introduce low level trap catching
    mips,kgdb: kdb low level trap catch and stack trace
    kgdb: Add the ability to schedule a breakpoint via a tasklet
    kgdboc,kdb: Allow kdb to work on a non open console port
    printk,kdb: capture printk() when in kdb shell
    keyboard, input: Add hook to input to allow low level event clear
    debug_core,kdb: Allow the debug core to process a recursive debug entry
    MAINTAINERS: update kgdb, kdb, and debug_core info
    kdb,debug_core: Allow the debug core to receive a panic notification
    kgdbts,sh: Add in breakpoint pc offset for superh
    debug_core: Turn off tracing while in the debugger

    Documentation/DocBook/kgdb.tmpl | 692 ++++++--
    Documentation/kernel-parameters.txt | 14 +-
    MAINTAINERS | 7 +-
    arch/arm/include/asm/kmap_types.h | 1 +
    arch/arm/kernel/kgdb.c | 5 +
    arch/blackfin/kernel/kgdb.c | 5 +
    arch/mips/include/asm/kgdb.h | 2 +
    arch/mips/kernel/kgdb.c | 27 +-
    arch/mips/kernel/traps.c | 13 +
    arch/powerpc/include/asm/kmap_types.h | 1 +
    arch/powerpc/kernel/kgdb.c | 11 +-
    arch/powerpc/kernel/traps.c | 7 +-
    arch/sh/kernel/kgdb.c | 14 +-
    arch/sparc/kernel/kgdb_32.c | 6 +
    arch/sparc/kernel/kgdb_64.c | 6 +
    arch/x86/include/asm/kgdb.h | 3 +
    arch/x86/kernel/kgdb.c | 56 +-
    arch/x86/kernel/traps.c | 6 +
    drivers/char/Makefile | 1 +
    drivers/char/kdb_keyboard.c | 204 +++
    drivers/char/kdb_keyboard.h | 143 ++
    drivers/char/keyboard.c | 29 +-
    drivers/input/input.c | 15 +
    drivers/misc/kgdbts.c | 6 +
    drivers/serial/8250.c | 4 +-
    drivers/serial/amba-pl011.c | 6 +-
    drivers/serial/kgdboc.c | 88 +-
    drivers/serial/sh-sci.c | 6 +-
    drivers/serial/sunzilog.c | 50 +
    include/asm-generic/kmap_types.h | 3 +-
    include/linux/input.h | 10 +
    include/linux/kdb.h | 117 ++
    include/linux/kgdb.h | 41 +-
    include/linux/serial_core.h | 1 +
    init/main.c | 2 +
    kernel/Makefile | 2 +-
    kernel/debug/Makefile | 7 +
    kernel/debug/debug_core.c | 967 +++++++++++
    kernel/debug/debug_core.h | 81 +
    kernel/debug/gdbstub.c | 1022 ++++++++++++
    kernel/debug/kdb/.gitignore | 1 +
    kernel/debug/kdb/Makefile | 24 +
    kernel/debug/kdb/kdb_bp.c | 564 +++++++
    kernel/debug/kdb/kdb_bt.c | 210 +++
    kernel/debug/kdb/kdb_cmds | 35 +
    kernel/debug/kdb/kdb_debugger.c | 169 ++
    kernel/debug/kdb/kdb_io.c | 826 ++++++++++
    kernel/debug/kdb/kdb_main.c | 2852 +++++++++++++++++++++++++++++++++
    kernel/debug/kdb/kdb_private.h | 300 ++++
    kernel/debug/kdb/kdb_support.c | 926 +++++++++++
    kernel/kallsyms.c | 21 +
    kernel/kgdb.c | 1763 --------------------
    kernel/module.c | 4 +
    kernel/printk.c | 25 +
    kernel/sched.c | 7 +-
    kernel/signal.c | 40 +
    lib/Kconfig.kgdb | 24 +-
    57 files changed, 9452 insertions(+), 2020 deletions(-)
    create mode 100644 drivers/char/kdb_keyboard.c
    create mode 100644 drivers/char/kdb_keyboard.h
    create mode 100644 include/linux/kdb.h
    create mode 100644 kernel/debug/Makefile
    create mode 100644 kernel/debug/debug_core.c
    create mode 100644 kernel/debug/debug_core.h
    create mode 100644 kernel/debug/gdbstub.c
    create mode 100644 kernel/debug/kdb/.gitignore
    create mode 100644 kernel/debug/kdb/Makefile
    create mode 100644 kernel/debug/kdb/kdb_bp.c
    create mode 100644 kernel/debug/kdb/kdb_bt.c
    create mode 100644 kernel/debug/kdb/kdb_cmds
    create mode 100644 kernel/debug/kdb/kdb_debugger.c
    create mode 100644 kernel/debug/kdb/kdb_io.c
    create mode 100644 kernel/debug/kdb/kdb_main.c
    create mode 100644 kernel/debug/kdb/kdb_private.h
    create mode 100644 kernel/debug/kdb/kdb_support.c
    delete mode 100644 kernel/kgdb.c

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      Last update: 2010-02-25 22:31    [W:0.058 / U:1.976 seconds]
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