[GIT PULL] V2 kdb / early debug (1 of 2) for 2.6.34
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From: Jason Wessel on 1 Mar 2010 00:20 Linus please pull the kdb-merge tree which merges the kdb front end into the kernel debug core for 7 architectures. git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.git kdb-merge --- Notes for Linus --- V2 of the pull request fixed up the patches per the input maintainer's comments, and there are presently no patches in the series with outstanding disputes. Specifically, this meant cleaning up the kdb keyboard code, and dropping the key release patch for now. 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 arch/x86/kernel/traps.c changes in which case I received no response at all. 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://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.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 window. 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: http://kernel.org/pub/linux/kernel/people/jwessel/kdb/ 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 allocator * 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. http://kgdb.wiki.kernel.org/index.php/Main_Page#Linux_Plumbers_Conference_presentation_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 implemented. The directory of the kernel debugger changed as well. All the kernel debugger pieces, the debug core, gdbstub and kdb now live under kernel/debug. 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: ftp://oss.sgi.com/projects/kdb/download/v4.4/ In the kernel .config you should enable the following options: CONFIG_KGDB=y CONFIG_KGDB_SERIAL_CONSOLE=y CONFIG_KGDB_LOW_LEVEL_TRAP=y CONFIG_KGDB_KDB=y CONFIG_KDB_KEYBOARD=y 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 commands. 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. Thanks, Jason. --- The following changes since commit 30ff056c42c665b9ea535d8515890857ae382540: Linus Torvalds (1): Merge branch 'x86-uv-for-linus' of git://git.kernel.org/.../tip/linux-2.6-tip are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.git kdb-merge Jason Wessel (27): 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 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/misc/kgdbts.c | 6 + drivers/serial/8250.c | 4 +- drivers/serial/amba-pl011.c | 6 +- drivers/serial/kgdboc.c | 75 +- drivers/serial/sh-sci.c | 6 +- drivers/serial/sunzilog.c | 50 + include/asm-generic/kmap_types.h | 3 +- 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 | 25 + 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_keyboard.c | 212 +++ 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 +- 52 files changed, 9255 insertions(+), 2015 deletions(-) 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_keyboard.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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Dmitry Torokhov on 22 Mar 2010 17:30
On Monday 22 March 2010 01:13:07 pm Jason Wessel wrote: > On 03/22/2010 03:05 PM, Jesse Barnes wrote: > > On Sat, 20 Mar 2010 21:14:24 -0500 > > > > Jason Wessel <jason.wessel(a)windriver.com> wrote: > >> On 02/28/2010 11:09 PM, Jason Wessel wrote: > >>> Linus please pull the kdb-merge tree which merges the kdb front end > >>> into the kernel debug core for 7 architectures. > >>> > >>> git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb.gi > >>> t kdb-merge > >> > >> What is the status of this pull request? Was some part of the process > >> missed here that there has been no response on this pull request? > >> > >> Please let me know what is wrong here. I have a number of other fixes > >> pending to the tree at this point. > >> > >> Would it be possible to merge part of the tree that is only related to > >> kgdb, in particular the directory re-organization? > > > > IIRC he still had some issues with the keyboard/input handling. We > > discussed it briefly a couple of weeks ago and he was worried about > > potential duplication. > > I worked with Dmitry Torokhov to come to some agreement with respect to > the kdb keyboard handling. This resulted in dropping one of the > keyboard patches entirely, and it will be done another way. There are > RFC patches from me on this, as well as Dmitry's own RFC patches for > sysrq handling. > > The discussion with Dmitry also resulted in the cleanup of the current > kdb low level PS/2 kdb keyboard driver to an acceptable state. I was > waiting to hear back on the response to the pull request before > investing further effort here. I am always open to suggestions of how > to solve this tricky problem. > Yep, as far as input concerned I am satisfied with Jason's changes so no need to block pull request on my account. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |