[PATCH v9 00/23] Add gdb python scripts as kernel debugging helpers

[PATCH v9 00/23] Add gdb python scripts as kernel debugging helpers

[Jan Kiszka]

Another refresh of this feature series. Changes since v8:
 - Ignore byte-compiled python files [Daniel Thompson]
 - rebase over recent Linux version, resolving a trivial conflict

See http://lkml.indiana.edu/hypermail/linux/kernel/1210.0/01598.html for
the original description and

    git://git.kiszka.org/linux.git queues/gdb-scripts

for the latest version.

Note that there is apparently some issue with gdb 7.8 and newer that
prevents lx-symbols from working here [1]. 7.7 is still fine, though.

Jan

[1] http://thread.gmane.org/gmane.comp.gdb.devel/34898

CC: Daniel Thompson <daniel.thompson@linaro.org>
CC: "David S. Miller" <davem@davemloft.net>
CC: Fenghua Yu <fenghua.yu@intel.com>
CC: Kay Sievers <kay@vrfy.org>
CC: linux-doc@vger.kernel.org
CC: linux-ia64@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
CC: linux-kbuild@vger.kernel.org
Cc: Michal Marek <mmarek@suse.cz>
CC: Michal Marek <mmarek@suse.cz>
CC: Pantelis Koukousoulas <pktoss@gmail.com>
CC: Rob Landley <rob@landley.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: sparclinux@vger.kernel.org
CC: Tony Luck <tony.luck@intel.com>

Daniel Thompson (1):
  scripts/gdb: Ignore byte-compiled python files

Jan Kiszka (21):
  scripts/gdb: Add infrastructure
  scripts/gdb: Add cache for type objects
  scripts/gdb: Add container_of helper and convenience function
  scripts/gdb: Add module iteration class
  scripts/gdb: Add lx-symbols command
  module: Do not inline do_init_module
  scripts/gdb: Add automatic symbol reloading on module insertion
  scripts/gdb: Add internal helper and convenience function to look up a
    module
  scripts/gdb: Add get_target_endianness helper
  scripts/gdb: Add read_u16/32/64 helpers
  scripts/gdb: Add lx-dmesg command
  scripts/gdb: Add task iteration class
  scripts/gdb: Add helper and convenience function to look up tasks
  scripts/gdb: Add is_target_arch helper
  scripts/gdb: Add internal helper and convenience function to retrieve
    thread_info
  scripts/gdb: Add get_gdbserver_type helper
  scripts/gdb: Add internal helper and convenience function for per-cpu
    lookup
  scripts/gdb: Add lx_current convenience function
  scripts/gdb: Add class to iterate over CPU masks
  scripts/gdb: Add lx-lsmod command
  scripts/gdb: Add basic documentation

Pantelis Koukousoulas (1):
  scripts/gdb: Port to python3 / gdb7.7

 .gitignore                             |   1 +
 Documentation/gdb-kernel-debugging.txt | 160 +++++++++++++++++++++++++++++++
 Makefile                               |   6 +-
 kernel/module.c                        |   9 +-
 lib/Kconfig.debug                      |  11 +++
 scripts/Makefile                       |   3 +-
 scripts/gdb/Makefile                   |   1 +
 scripts/gdb/linux/.gitignore           |   2 +
 scripts/gdb/linux/Makefile             |  11 +++
 scripts/gdb/linux/__init__.py          |   0
 scripts/gdb/linux/cpus.py              | 142 ++++++++++++++++++++++++++++
 scripts/gdb/linux/dmesg.py             |  65 +++++++++++++
 scripts/gdb/linux/modules.py           | 114 ++++++++++++++++++++++
 scripts/gdb/linux/symbols.py           | 166 +++++++++++++++++++++++++++++++++
 scripts/gdb/linux/tasks.py             | 110 ++++++++++++++++++++++
 scripts/gdb/linux/utils.py             | 156 +++++++++++++++++++++++++++++++
 scripts/gdb/vmlinux-gdb.py             |  30 ++++++
 17 files changed, 983 insertions(+), 4 deletions(-)
 create mode 100644 Documentation/gdb-kernel-debugging.txt
 create mode 100644 scripts/gdb/Makefile
 create mode 100644 scripts/gdb/linux/.gitignore
 create mode 100644 scripts/gdb/linux/Makefile
 create mode 100644 scripts/gdb/linux/__init__.py
 create mode 100644 scripts/gdb/linux/cpus.py
 create mode 100644 scripts/gdb/linux/dmesg.py
 create mode 100644 scripts/gdb/linux/modules.py
 create mode 100644 scripts/gdb/linux/symbols.py
 create mode 100644 scripts/gdb/linux/tasks.py
 create mode 100644 scripts/gdb/linux/utils.py
 create mode 100644 scripts/gdb/vmlinux-gdb.py

-- 
1.8.1.1.298.ge7eed54

[PATCH v9 01/23] scripts/gdb: Add infrastructure

[Jan Kiszka]

This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.

The loading mechanism is based on gdb loading for <objfile>-gdb.py when
opening <objfile>. Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.

The main scripts will pull in submodules containing Linux specific gdb
commands and functions. To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.

Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.

This feature is enabled via CONFIG_GDB_SCRIPTS.

CC: Michal Marek <mmarek@suse.cz>
CC: linux-kbuild@vger.kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 Makefile                      |  6 +++++-
 lib/Kconfig.debug             | 11 +++++++++++
 scripts/Makefile              |  3 ++-
 scripts/gdb/Makefile          |  1 +
 scripts/gdb/linux/Makefile    | 11 +++++++++++
 scripts/gdb/linux/__init__.py |  0
 scripts/gdb/vmlinux-gdb.py    | 23 +++++++++++++++++++++++
 7 files changed, 53 insertions(+), 2 deletions(-)
 create mode 100644 scripts/gdb/Makefile
 create mode 100644 scripts/gdb/linux/Makefile
 create mode 100644 scripts/gdb/linux/__init__.py
 create mode 100644 scripts/gdb/vmlinux-gdb.py

diff --git a/Makefile b/Makefile
index f64fc78..6cddc6f 100644
--- a/Makefile
+++ b/Makefile
@@ -912,6 +912,9 @@ endif
 ifdef CONFIG_BUILD_DOCSRC
 	$(Q)$(MAKE) $(build)=Documentation
 endif
+ifdef CONFIG_GDB_SCRIPTS
+	$(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
+endif
 	+$(call if_changed,link-vmlinux)
 
 # The actual objects are generated when descending,
@@ -1167,7 +1170,8 @@ MRPROPER_FILES += .config .config.old .version .old_version $(version_h) \
 		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
 		  signing_key.priv signing_key.x509 x509.genkey		\
 		  extra_certificates signing_key.x509.keyid		\
-		  signing_key.x509.signer include/linux/version.h
+		  signing_key.x509.signer include/linux/version.h	\
+		  vmlinux-gdb.py
 
 # clean - Delete most, but leave enough to build external modules
 #
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 07c2832..ab79d9b 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -167,6 +167,17 @@ config DEBUG_INFO_DWARF4
 	  But it significantly improves the success of resolving
 	  variables in gdb on optimized code.
 
+config GDB_SCRIPTS
+	bool "Provide GDB scripts for kernel debugging"
+	select DEBUG_INFO
+	help
+	  This creates the required links to GDB helper scripts in the
+	  build directory. If you load vmlinux into gdb, the helper
+	  scripts will be automatically imported by gdb as well, and
+	  additional functions are available to analyze a Linux kernel
+	  instance. See Documentation/gdb-kernel-debugging.txt for further
+	  details.
+
 config ENABLE_WARN_DEPRECATED
 	bool "Enable __deprecated logic"
 	default y
diff --git a/scripts/Makefile b/scripts/Makefile
index 72902b5..7413b1b 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -36,6 +36,7 @@ subdir-$(CONFIG_MODVERSIONS) += genksyms
 subdir-y                     += mod
 subdir-$(CONFIG_SECURITY_SELINUX) += selinux
 subdir-$(CONFIG_DTC)         += dtc
+subdir-$(CONFIG_GDB_SCRIPTS) += gdb
 
 # Let clean descend into subdirs
-subdir-	+= basic kconfig package
+subdir-	+= basic kconfig package gdb
diff --git a/scripts/gdb/Makefile b/scripts/gdb/Makefile
new file mode 100644
index 0000000..62f5f65
--- /dev/null
+++ b/scripts/gdb/Makefile
@@ -0,0 +1 @@
+subdir-y := linux
diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
new file mode 100644
index 0000000..dcb63ab
--- /dev/null
+++ b/scripts/gdb/linux/Makefile
@@ -0,0 +1,11 @@
+always := gdb-scripts
+
+SRCTREE := $(shell cd $(srctree) && /bin/pwd)
+
+$(obj)/gdb-scripts:
+ifneq ($(KBUILD_SRC),)
+	$(Q)ln -fsn $(SRCTREE)/$(obj)/*.py $(objtree)/$(obj)
+endif
+	@:
+
+clean-files := *.pyc $(if $(KBUILD_SRC),*.py)
diff --git a/scripts/gdb/linux/__init__.py b/scripts/gdb/linux/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py
new file mode 100644
index 0000000..c1d90ce
--- /dev/null
+++ b/scripts/gdb/vmlinux-gdb.py
@@ -0,0 +1,23 @@
+#
+# gdb helper commands and functions for Linux kernel debugging
+#
+#  loader module
+#
+# Copyright (c) Siemens AG, 2012, 2013
+#
+# Authors:
+#  Jan Kiszka <jan.kiszka@siemens.com>
+#
+# This work is licensed under the terms of the GNU GPL version 2.
+#
+
+import os
+
+sys.path.insert(0, os.path.dirname(__file__) + "/scripts/gdb")
+
+try:
+    gdb.parse_and_eval("0")
+    gdb.execute("", to_string=True)
+except:
+    gdb.write("NOTE: gdb 7.2 or later required for Linux helper scripts to "
+              "work.\n")
-- 
1.8.1.1.298.ge7eed54

[PATCH v9 23/23] scripts/gdb: Ignore byte-compiled python files

[Jan Kiszka]

From: Daniel Thompson <daniel.thompson@linaro.org>

Using the gdb scripts leaves byte-compiled python files in the scripts/
directory. These should be ignored by git and cleaned up by mrproper.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 .gitignore                   | 1 +
 Makefile                     | 2 +-
 scripts/gdb/linux/.gitignore | 2 ++
 3 files changed, 4 insertions(+), 1 deletion(-)
 create mode 100644 scripts/gdb/linux/.gitignore

diff --git a/.gitignore b/.gitignore
index e213b27..17d4457 100644
--- a/.gitignore
+++ b/.gitignore
@@ -43,6 +43,7 @@ Module.symvers
 /TAGS
 /linux
 /vmlinux
+/vmlinux-gdb.py
 /vmlinuz
 /System.map
 /Module.markers
diff --git a/Makefile b/Makefile
index 6cddc6f..d319e25 100644
--- a/Makefile
+++ b/Makefile
@@ -1171,7 +1171,7 @@ MRPROPER_FILES += .config .config.old .version .old_version $(version_h) \
 		  signing_key.priv signing_key.x509 x509.genkey		\
 		  extra_certificates signing_key.x509.keyid		\
 		  signing_key.x509.signer include/linux/version.h	\
-		  vmlinux-gdb.py
+		  vmlinux-gdb.py scripts/gdb/linux/*.py[co]
 
 # clean - Delete most, but leave enough to build external modules
 #
diff --git a/scripts/gdb/linux/.gitignore b/scripts/gdb/linux/.gitignore
new file mode 100644
index 0000000..52e4e61
--- /dev/null
+++ b/scripts/gdb/linux/.gitignore
@@ -0,0 +1,2 @@
+*.pyc
+*.pyo
-- 
1.8.1.1.298.ge7eed54