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diff --git a/Documentation/dev-tools/coccinelle.rst b/Documentation/dev-tools/coccinelle.rst
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index 000000000000..4a64b4c69d3f
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+.. Copyright 2010 Nicolas Palix <npalix@diku.dk>
+.. Copyright 2010 Julia Lawall <julia@diku.dk>
+.. Copyright 2010 Gilles Muller <Gilles.Muller@lip6.fr>
+
+.. highlight:: none
+
+Coccinelle
+==========
+
+Coccinelle is a tool for pattern matching and text transformation that has
+many uses in kernel development, including the application of complex,
+tree-wide patches and detection of problematic programming patterns.
+
+Getting Coccinelle
+-------------------
+
+The semantic patches included in the kernel use features and options
+which are provided by Coccinelle version 1.0.0-rc11 and above.
+Using earlier versions will fail as the option names used by
+the Coccinelle files and coccicheck have been updated.
+
+Coccinelle is available through the package manager
+of many distributions, e.g. :
+
+ - Debian
+ - Fedora
+ - Ubuntu
+ - OpenSUSE
+ - Arch Linux
+ - NetBSD
+ - FreeBSD
+
+You can get the latest version released from the Coccinelle homepage at
+http://coccinelle.lip6.fr/
+
+Information and tips about Coccinelle are also provided on the wiki
+pages at http://cocci.ekstranet.diku.dk/wiki/doku.php
+
+Once you have it, run the following command::
+
+     	./configure
+        make
+
+as a regular user, and install it with::
+
+        sudo make install
+
+Supplemental documentation
+---------------------------
+
+For supplemental documentation refer to the wiki:
+
+https://bottest.wiki.kernel.org/coccicheck
+
+The wiki documentation always refers to the linux-next version of the script.
+
+Using Coccinelle on the Linux kernel
+------------------------------------
+
+A Coccinelle-specific target is defined in the top level
+Makefile. This target is named ``coccicheck`` and calls the ``coccicheck``
+front-end in the ``scripts`` directory.
+
+Four basic modes are defined: ``patch``, ``report``, ``context``, and
+``org``. The mode to use is specified by setting the MODE variable with
+``MODE=<mode>``.
+
+- ``patch`` proposes a fix, when possible.
+
+- ``report`` generates a list in the following format:
+  file:line:column-column: message
+
+- ``context`` highlights lines of interest and their context in a
+  diff-like style.Lines of interest are indicated with ``-``.
+
+- ``org`` generates a report in the Org mode format of Emacs.
+
+Note that not all semantic patches implement all modes. For easy use
+of Coccinelle, the default mode is "report".
+
+Two other modes provide some common combinations of these modes.
+
+- ``chain`` tries the previous modes in the order above until one succeeds.
+
+- ``rep+ctxt`` runs successively the report mode and the context mode.
+  It should be used with the C option (described later)
+  which checks the code on a file basis.
+
+Examples
+~~~~~~~~
+
+To make a report for every semantic patch, run the following command::
+
+		make coccicheck MODE=report
+
+To produce patches, run::
+
+		make coccicheck MODE=patch
+
+
+The coccicheck target applies every semantic patch available in the
+sub-directories of ``scripts/coccinelle`` to the entire Linux kernel.
+
+For each semantic patch, a commit message is proposed.  It gives a
+description of the problem being checked by the semantic patch, and
+includes a reference to Coccinelle.
+
+As any static code analyzer, Coccinelle produces false
+positives. Thus, reports must be carefully checked, and patches
+reviewed.
+
+To enable verbose messages set the V= variable, for example::
+
+   make coccicheck MODE=report V=1
+
+Coccinelle parallelization
+---------------------------
+
+By default, coccicheck tries to run as parallel as possible. To change
+the parallelism, set the J= variable. For example, to run across 4 CPUs::
+
+   make coccicheck MODE=report J=4
+
+As of Coccinelle 1.0.2 Coccinelle uses Ocaml parmap for parallelization,
+if support for this is detected you will benefit from parmap parallelization.
+
+When parmap is enabled coccicheck will enable dynamic load balancing by using
+``--chunksize 1`` argument, this ensures we keep feeding threads with work
+one by one, so that we avoid the situation where most work gets done by only
+a few threads. With dynamic load balancing, if a thread finishes early we keep
+feeding it more work.
+
+When parmap is enabled, if an error occurs in Coccinelle, this error
+value is propagated back, the return value of the ``make coccicheck``
+captures this return value.
+
+Using Coccinelle with a single semantic patch
+---------------------------------------------
+
+The optional make variable COCCI can be used to check a single
+semantic patch. In that case, the variable must be initialized with
+the name of the semantic patch to apply.
+
+For instance::
+
+	make coccicheck COCCI=<my_SP.cocci> MODE=patch
+
+or::
+
+	make coccicheck COCCI=<my_SP.cocci> MODE=report
+
+
+Controlling Which Files are Processed by Coccinelle
+---------------------------------------------------
+
+By default the entire kernel source tree is checked.
+
+To apply Coccinelle to a specific directory, ``M=`` can be used.
+For example, to check drivers/net/wireless/ one may write::
+
+    make coccicheck M=drivers/net/wireless/
+
+To apply Coccinelle on a file basis, instead of a directory basis, the
+following command may be used::
+
+    make C=1 CHECK="scripts/coccicheck"
+
+To check only newly edited code, use the value 2 for the C flag, i.e.::
+
+    make C=2 CHECK="scripts/coccicheck"
+
+In these modes, which works on a file basis, there is no information
+about semantic patches displayed, and no commit message proposed.
+
+This runs every semantic patch in scripts/coccinelle by default. The
+COCCI variable may additionally be used to only apply a single
+semantic patch as shown in the previous section.
+
+The "report" mode is the default. You can select another one with the
+MODE variable explained above.
+
+Debugging Coccinelle SmPL patches
+---------------------------------
+
+Using coccicheck is best as it provides in the spatch command line
+include options matching the options used when we compile the kernel.
+You can learn what these options are by using V=1, you could then
+manually run Coccinelle with debug options added.
+
+Alternatively you can debug running Coccinelle against SmPL patches
+by asking for stderr to be redirected to stderr, by default stderr
+is redirected to /dev/null, if you'd like to capture stderr you
+can specify the ``DEBUG_FILE="file.txt"`` option to coccicheck. For
+instance::
+
+    rm -f cocci.err
+    make coccicheck COCCI=scripts/coccinelle/free/kfree.cocci MODE=report DEBUG_FILE=cocci.err
+    cat cocci.err
+
+You can use SPFLAGS to add debugging flags, for instance you may want to
+add both --profile --show-trying to SPFLAGS when debugging. For instance
+you may want to use::
+
+    rm -f err.log
+    export COCCI=scripts/coccinelle/misc/irqf_oneshot.cocci
+    make coccicheck DEBUG_FILE="err.log" MODE=report SPFLAGS="--profile --show-trying" M=./drivers/mfd/arizona-irq.c
+
+err.log will now have the profiling information, while stdout will
+provide some progress information as Coccinelle moves forward with
+work.
+
+DEBUG_FILE support is only supported when using coccinelle >= 1.2.
+
+.cocciconfig support
+--------------------
+
+Coccinelle supports reading .cocciconfig for default Coccinelle options that
+should be used every time spatch is spawned, the order of precedence for
+variables for .cocciconfig is as follows:
+
+- Your current user's home directory is processed first
+- Your directory from which spatch is called is processed next
+- The directory provided with the --dir option is processed last, if used
+
+Since coccicheck runs through make, it naturally runs from the kernel
+proper dir, as such the second rule above would be implied for picking up a
+.cocciconfig when using ``make coccicheck``.
+
+``make coccicheck`` also supports using M= targets.If you do not supply
+any M= target, it is assumed you want to target the entire kernel.
+The kernel coccicheck script has::
+
+    if [ "$KBUILD_EXTMOD" = "" ] ; then
+        OPTIONS="--dir $srctree $COCCIINCLUDE"
+    else
+        OPTIONS="--dir $KBUILD_EXTMOD $COCCIINCLUDE"
+    fi
+
+KBUILD_EXTMOD is set when an explicit target with M= is used. For both cases
+the spatch --dir argument is used, as such third rule applies when whether M=
+is used or not, and when M= is used the target directory can have its own
+.cocciconfig file. When M= is not passed as an argument to coccicheck the
+target directory is the same as the directory from where spatch was called.
+
+If not using the kernel's coccicheck target, keep the above precedence
+order logic of .cocciconfig reading. If using the kernel's coccicheck target,
+override any of the kernel's .coccicheck's settings using SPFLAGS.
+
+We help Coccinelle when used against Linux with a set of sensible defaults
+options for Linux with our own Linux .cocciconfig. This hints to coccinelle
+git can be used for ``git grep`` queries over coccigrep. A timeout of 200
+seconds should suffice for now.
+
+The options picked up by coccinelle when reading a .cocciconfig do not appear
+as arguments to spatch processes running on your system, to confirm what
+options will be used by Coccinelle run::
+
+      spatch --print-options-only
+
+You can override with your own preferred index option by using SPFLAGS. Take
+note that when there are conflicting options Coccinelle takes precedence for
+the last options passed. Using .cocciconfig is possible to use idutils, however
+given the order of precedence followed by Coccinelle, since the kernel now
+carries its own .cocciconfig, you will need to use SPFLAGS to use idutils if
+desired. See below section "Additional flags" for more details on how to use
+idutils.
+
+Additional flags
+----------------
+
+Additional flags can be passed to spatch through the SPFLAGS
+variable. This works as Coccinelle respects the last flags
+given to it when options are in conflict. ::
+
+    make SPFLAGS=--use-glimpse coccicheck
+
+Coccinelle supports idutils as well but requires coccinelle >= 1.0.6.
+When no ID file is specified coccinelle assumes your ID database file
+is in the file .id-utils.index on the top level of the kernel, coccinelle
+carries a script scripts/idutils_index.sh which creates the database with::
+
+    mkid -i C --output .id-utils.index
+
+If you have another database filename you can also just symlink with this
+name. ::
+
+    make SPFLAGS=--use-idutils coccicheck
+
+Alternatively you can specify the database filename explicitly, for
+instance::
+
+    make SPFLAGS="--use-idutils /full-path/to/ID" coccicheck
+
+See ``spatch --help`` to learn more about spatch options.
+
+Note that the ``--use-glimpse`` and ``--use-idutils`` options
+require external tools for indexing the code. None of them is
+thus active by default. However, by indexing the code with
+one of these tools, and according to the cocci file used,
+spatch could proceed the entire code base more quickly.
+
+SmPL patch specific options
+---------------------------
+
+SmPL patches can have their own requirements for options passed
+to Coccinelle. SmPL patch specific options can be provided by
+providing them at the top of the SmPL patch, for instance::
+
+	// Options: --no-includes --include-headers
+
+SmPL patch Coccinelle requirements
+----------------------------------
+
+As Coccinelle features get added some more advanced SmPL patches
+may require newer versions of Coccinelle. If an SmPL patch requires
+at least a version of Coccinelle, this can be specified as follows,
+as an example if requiring at least Coccinelle >= 1.0.5::
+
+	// Requires: 1.0.5
+
+Proposing new semantic patches
+-------------------------------
+
+New semantic patches can be proposed and submitted by kernel
+developers. For sake of clarity, they should be organized in the
+sub-directories of ``scripts/coccinelle/``.
+
+
+Detailed description of the ``report`` mode
+-------------------------------------------
+
+``report`` generates a list in the following format::
+
+  file:line:column-column: message
+
+Example
+~~~~~~~
+
+Running::
+
+	make coccicheck MODE=report COCCI=scripts/coccinelle/api/err_cast.cocci
+
+will execute the following part of the SmPL script::
+
+   <smpl>
+   @r depends on !context && !patch && (org || report)@
+   expression x;
+   position p;
+   @@
+
+     ERR_PTR@p(PTR_ERR(x))
+
+   @script:python depends on report@
+   p << r.p;
+   x << r.x;
+   @@
+
+   msg="ERR_CAST can be used with %s" % (x)
+   coccilib.report.print_report(p[0], msg)
+   </smpl>
+
+This SmPL excerpt generates entries on the standard output, as
+illustrated below::
+
+    /home/user/linux/crypto/ctr.c:188:9-16: ERR_CAST can be used with alg
+    /home/user/linux/crypto/authenc.c:619:9-16: ERR_CAST can be used with auth
+    /home/user/linux/crypto/xts.c:227:9-16: ERR_CAST can be used with alg
+
+
+Detailed description of the ``patch`` mode
+------------------------------------------
+
+When the ``patch`` mode is available, it proposes a fix for each problem
+identified.
+
+Example
+~~~~~~~
+
+Running::
+
+	make coccicheck MODE=patch COCCI=scripts/coccinelle/api/err_cast.cocci
+
+will execute the following part of the SmPL script::
+
+    <smpl>
+    @ depends on !context && patch && !org && !report @
+    expression x;
+    @@
+
+    - ERR_PTR(PTR_ERR(x))
+    + ERR_CAST(x)
+    </smpl>
+
+This SmPL excerpt generates patch hunks on the standard output, as
+illustrated below::
+
+    diff -u -p a/crypto/ctr.c b/crypto/ctr.c
+    --- a/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
+    +++ b/crypto/ctr.c 2010-06-03 23:44:49.000000000 +0200
+    @@ -185,7 +185,7 @@ static struct crypto_instance *crypto_ct
+ 	alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
+ 				  CRYPTO_ALG_TYPE_MASK);
+ 	if (IS_ERR(alg))
+    -		return ERR_PTR(PTR_ERR(alg));
+    +		return ERR_CAST(alg);
+
+ 	/* Block size must be >= 4 bytes. */
+ 	err = -EINVAL;
+
+Detailed description of the ``context`` mode
+--------------------------------------------
+
+``context`` highlights lines of interest and their context
+in a diff-like style.
+
+      **NOTE**: The diff-like output generated is NOT an applicable patch. The
+      intent of the ``context`` mode is to highlight the important lines
+      (annotated with minus, ``-``) and gives some surrounding context
+      lines around. This output can be used with the diff mode of
+      Emacs to review the code.
+
+Example
+~~~~~~~
+
+Running::
+
+	make coccicheck MODE=context COCCI=scripts/coccinelle/api/err_cast.cocci
+
+will execute the following part of the SmPL script::
+
+    <smpl>
+    @ depends on context && !patch && !org && !report@
+    expression x;
+    @@
+
+    * ERR_PTR(PTR_ERR(x))
+    </smpl>
+
+This SmPL excerpt generates diff hunks on the standard output, as
+illustrated below::
+
+    diff -u -p /home/user/linux/crypto/ctr.c /tmp/nothing
+    --- /home/user/linux/crypto/ctr.c	2010-05-26 10:49:38.000000000 +0200
+    +++ /tmp/nothing
+    @@ -185,7 +185,6 @@ static struct crypto_instance *crypto_ct
+ 	alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
+ 				  CRYPTO_ALG_TYPE_MASK);
+ 	if (IS_ERR(alg))
+    -		return ERR_PTR(PTR_ERR(alg));
+
+ 	/* Block size must be >= 4 bytes. */
+ 	err = -EINVAL;
+
+Detailed description of the ``org`` mode
+----------------------------------------
+
+``org`` generates a report in the Org mode format of Emacs.
+
+Example
+~~~~~~~
+
+Running::
+
+	make coccicheck MODE=org COCCI=scripts/coccinelle/api/err_cast.cocci
+
+will execute the following part of the SmPL script::
+
+    <smpl>
+    @r depends on !context && !patch && (org || report)@
+    expression x;
+    position p;
+    @@
+
+      ERR_PTR@p(PTR_ERR(x))
+
+    @script:python depends on org@
+    p << r.p;
+    x << r.x;
+    @@
+
+    msg="ERR_CAST can be used with %s" % (x)
+    msg_safe=msg.replace("[","@(").replace("]",")")
+    coccilib.org.print_todo(p[0], msg_safe)
+    </smpl>
+
+This SmPL excerpt generates Org entries on the standard output, as
+illustrated below::
+
+    * TODO [[view:/home/user/linux/crypto/ctr.c::face=ovl-face1::linb=188::colb=9::cole=16][ERR_CAST can be used with alg]]
+    * TODO [[view:/home/user/linux/crypto/authenc.c::face=ovl-face1::linb=619::colb=9::cole=16][ERR_CAST can be used with auth]]
+    * TODO [[view:/home/user/linux/crypto/xts.c::face=ovl-face1::linb=227::colb=9::cole=16][ERR_CAST can be used with alg]]
diff --git a/Documentation/dev-tools/gcov.rst b/Documentation/dev-tools/gcov.rst
new file mode 100644
index 000000000000..19eedfea8800
--- /dev/null
+++ b/Documentation/dev-tools/gcov.rst
@@ -0,0 +1,256 @@
+Using gcov with the Linux kernel
+================================
+
+gcov profiling kernel support enables the use of GCC's coverage testing
+tool gcov_ with the Linux kernel. Coverage data of a running kernel
+is exported in gcov-compatible format via the "gcov" debugfs directory.
+To get coverage data for a specific file, change to the kernel build
+directory and use gcov with the ``-o`` option as follows (requires root)::
+
+    # cd /tmp/linux-out
+    # gcov -o /sys/kernel/debug/gcov/tmp/linux-out/kernel spinlock.c
+
+This will create source code files annotated with execution counts
+in the current directory. In addition, graphical gcov front-ends such
+as lcov_ can be used to automate the process of collecting data
+for the entire kernel and provide coverage overviews in HTML format.
+
+Possible uses:
+
+* debugging (has this line been reached at all?)
+* test improvement (how do I change my test to cover these lines?)
+* minimizing kernel configurations (do I need this option if the
+  associated code is never run?)
+
+.. _gcov: http://gcc.gnu.org/onlinedocs/gcc/Gcov.html
+.. _lcov: http://ltp.sourceforge.net/coverage/lcov.php
+
+
+Preparation
+-----------
+
+Configure the kernel with::
+
+        CONFIG_DEBUG_FS=y
+        CONFIG_GCOV_KERNEL=y
+
+select the gcc's gcov format, default is autodetect based on gcc version::
+
+        CONFIG_GCOV_FORMAT_AUTODETECT=y
+
+and to get coverage data for the entire kernel::
+
+        CONFIG_GCOV_PROFILE_ALL=y
+
+Note that kernels compiled with profiling flags will be significantly
+larger and run slower. Also CONFIG_GCOV_PROFILE_ALL may not be supported
+on all architectures.
+
+Profiling data will only become accessible once debugfs has been
+mounted::
+
+        mount -t debugfs none /sys/kernel/debug
+
+
+Customization
+-------------
+
+To enable profiling for specific files or directories, add a line
+similar to the following to the respective kernel Makefile:
+
+- For a single file (e.g. main.o)::
+
+	GCOV_PROFILE_main.o := y
+
+- For all files in one directory::
+
+	GCOV_PROFILE := y
+
+To exclude files from being profiled even when CONFIG_GCOV_PROFILE_ALL
+is specified, use::
+
+	GCOV_PROFILE_main.o := n
+
+and::
+
+	GCOV_PROFILE := n
+
+Only files which are linked to the main kernel image or are compiled as
+kernel modules are supported by this mechanism.
+
+
+Files
+-----
+
+The gcov kernel support creates the following files in debugfs:
+
+``/sys/kernel/debug/gcov``
+	Parent directory for all gcov-related files.
+
+``/sys/kernel/debug/gcov/reset``
+	Global reset file: resets all coverage data to zero when
+        written to.
+
+``/sys/kernel/debug/gcov/path/to/compile/dir/file.gcda``
+	The actual gcov data file as understood by the gcov
+        tool. Resets file coverage data to zero when written to.
+
+``/sys/kernel/debug/gcov/path/to/compile/dir/file.gcno``
+	Symbolic link to a static data file required by the gcov
+        tool. This file is generated by gcc when compiling with
+        option ``-ftest-coverage``.
+
+
+Modules
+-------
+
+Kernel modules may contain cleanup code which is only run during
+module unload time. The gcov mechanism provides a means to collect
+coverage data for such code by keeping a copy of the data associated
+with the unloaded module. This data remains available through debugfs.
+Once the module is loaded again, the associated coverage counters are
+initialized with the data from its previous instantiation.
+
+This behavior can be deactivated by specifying the gcov_persist kernel
+parameter::
+
+        gcov_persist=0
+
+At run-time, a user can also choose to discard data for an unloaded
+module by writing to its data file or the global reset file.
+
+
+Separated build and test machines
+---------------------------------
+
+The gcov kernel profiling infrastructure is designed to work out-of-the
+box for setups where kernels are built and run on the same machine. In
+cases where the kernel runs on a separate machine, special preparations
+must be made, depending on where the gcov tool is used:
+
+a) gcov is run on the TEST machine
+
+    The gcov tool version on the test machine must be compatible with the
+    gcc version used for kernel build. Also the following files need to be
+    copied from build to test machine:
+
+    from the source tree:
+      - all C source files + headers
+
+    from the build tree:
+      - all C source files + headers
+      - all .gcda and .gcno files
+      - all links to directories
+
+    It is important to note that these files need to be placed into the
+    exact same file system location on the test machine as on the build
+    machine. If any of the path components is symbolic link, the actual
+    directory needs to be used instead (due to make's CURDIR handling).
+
+b) gcov is run on the BUILD machine
+
+    The following files need to be copied after each test case from test
+    to build machine:
+
+    from the gcov directory in sysfs:
+      - all .gcda files
+      - all links to .gcno files
+
+    These files can be copied to any location on the build machine. gcov
+    must then be called with the -o option pointing to that directory.
+
+    Example directory setup on the build machine::
+
+      /tmp/linux:    kernel source tree
+      /tmp/out:      kernel build directory as specified by make O=
+      /tmp/coverage: location of the files copied from the test machine
+
+      [user@build] cd /tmp/out
+      [user@build] gcov -o /tmp/coverage/tmp/out/init main.c
+
+
+Troubleshooting
+---------------
+
+Problem
+    Compilation aborts during linker step.
+
+Cause
+    Profiling flags are specified for source files which are not
+    linked to the main kernel or which are linked by a custom
+    linker procedure.
+
+Solution
+    Exclude affected source files from profiling by specifying
+    ``GCOV_PROFILE := n`` or ``GCOV_PROFILE_basename.o := n`` in the
+    corresponding Makefile.
+
+Problem
+    Files copied from sysfs appear empty or incomplete.
+
+Cause
+    Due to the way seq_file works, some tools such as cp or tar
+    may not correctly copy files from sysfs.
+
+Solution
+    Use ``cat``' to read ``.gcda`` files and ``cp -d`` to copy links.
+    Alternatively use the mechanism shown in Appendix B.
+
+
+Appendix A: gather_on_build.sh
+------------------------------
+
+Sample script to gather coverage meta files on the build machine
+(see 6a)::
+
+    #!/bin/bash
+
+    KSRC=$1
+    KOBJ=$2
+    DEST=$3
+
+    if [ -z "$KSRC" ] || [ -z "$KOBJ" ] || [ -z "$DEST" ]; then
+      echo "Usage: $0 <ksrc directory> <kobj directory> <output.tar.gz>" >&2
+      exit 1
+    fi
+
+    KSRC=$(cd $KSRC; printf "all:\n\t@echo \${CURDIR}\n" | make -f -)
+    KOBJ=$(cd $KOBJ; printf "all:\n\t@echo \${CURDIR}\n" | make -f -)
+
+    find $KSRC $KOBJ \( -name '*.gcno' -o -name '*.[ch]' -o -type l \) -a \
+                     -perm /u+r,g+r | tar cfz $DEST -P -T -
+
+    if [ $? -eq 0 ] ; then
+      echo "$DEST successfully created, copy to test system and unpack with:"
+      echo "  tar xfz $DEST -P"
+    else
+      echo "Could not create file $DEST"
+    fi
+
+
+Appendix B: gather_on_test.sh
+-----------------------------
+
+Sample script to gather coverage data files on the test machine
+(see 6b)::
+
+    #!/bin/bash -e
+
+    DEST=$1
+    GCDA=/sys/kernel/debug/gcov
+
+    if [ -z "$DEST" ] ; then
+      echo "Usage: $0 <output.tar.gz>" >&2
+      exit 1
+    fi
+
+    TEMPDIR=$(mktemp -d)
+    echo Collecting data..
+    find $GCDA -type d -exec mkdir -p $TEMPDIR/\{\} \;
+    find $GCDA -name '*.gcda' -exec sh -c 'cat < $0 > '$TEMPDIR'/$0' {} \;
+    find $GCDA -name '*.gcno' -exec sh -c 'cp -d $0 '$TEMPDIR'/$0' {} \;
+    tar czf $DEST -C $TEMPDIR sys
+    rm -rf $TEMPDIR
+
+    echo "$DEST successfully created, copy to build system and unpack with:"
+    echo "  tar xfz $DEST"
diff --git a/Documentation/dev-tools/gdb-kernel-debugging.rst b/Documentation/dev-tools/gdb-kernel-debugging.rst
new file mode 100644
index 000000000000..5e93c9bc6619
--- /dev/null
+++ b/Documentation/dev-tools/gdb-kernel-debugging.rst
@@ -0,0 +1,173 @@
+.. highlight:: none
+
+Debugging kernel and modules via gdb
+====================================
+
+The kernel debugger kgdb, hypervisors like QEMU or JTAG-based hardware
+interfaces allow to debug the Linux kernel and its modules during runtime
+using gdb. Gdb comes with a powerful scripting interface for python. The
+kernel provides a collection of helper scripts that can simplify typical
+kernel debugging steps. This is a short tutorial about how to enable and use
+them. It focuses on QEMU/KVM virtual machines as target, but the examples can
+be transferred to the other gdb stubs as well.
+
+
+Requirements
+------------
+
+- gdb 7.2+ (recommended: 7.4+) with python support enabled (typically true
+  for distributions)
+
+
+Setup
+-----
+
+- Create a virtual Linux machine for QEMU/KVM (see www.linux-kvm.org and
+  www.qemu.org for more details). For cross-development,
+  http://landley.net/aboriginal/bin keeps a pool of machine images and
+  toolchains that can be helpful to start from.
+
+- Build the kernel with CONFIG_GDB_SCRIPTS enabled, but leave
+  CONFIG_DEBUG_INFO_REDUCED off. If your architecture supports
+  CONFIG_FRAME_POINTER, keep it enabled.
+
+- Install that kernel on the guest.
+  Alternatively, QEMU allows to boot the kernel directly using -kernel,
+  -append, -initrd command line switches. This is generally only useful if
+  you do not depend on modules. See QEMU documentation for more details on
+  this mode.
+
+- Enable the gdb stub of QEMU/KVM, either
+
+    - at VM startup time by appending "-s" to the QEMU command line
+
+  or
+
+    - during runtime by issuing "gdbserver" from the QEMU monitor
+      console
+
+- cd /path/to/linux-build
+
+- Start gdb: gdb vmlinux
+
+  Note: Some distros may restrict auto-loading of gdb scripts to known safe
+  directories. In case gdb reports to refuse loading vmlinux-gdb.py, add::
+
+    add-auto-load-safe-path /path/to/linux-build
+
+  to ~/.gdbinit. See gdb help for more details.
+
+- Attach to the booted guest::
+
+    (gdb) target remote :1234
+
+
+Examples of using the Linux-provided gdb helpers
+------------------------------------------------
+
+- Load module (and main kernel) symbols::
+
+    (gdb) lx-symbols
+    loading vmlinux
+    scanning for modules in /home/user/linux/build
+    loading @0xffffffffa0020000: /home/user/linux/build/net/netfilter/xt_tcpudp.ko
+    loading @0xffffffffa0016000: /home/user/linux/build/net/netfilter/xt_pkttype.ko
+    loading @0xffffffffa0002000: /home/user/linux/build/net/netfilter/xt_limit.ko
+    loading @0xffffffffa00ca000: /home/user/linux/build/net/packet/af_packet.ko
+    loading @0xffffffffa003c000: /home/user/linux/build/fs/fuse/fuse.ko
+    ...
+    loading @0xffffffffa0000000: /home/user/linux/build/drivers/ata/ata_generic.ko
+
+- Set a breakpoint on some not yet loaded module function, e.g.::
+
+    (gdb) b btrfs_init_sysfs
+    Function "btrfs_init_sysfs" not defined.
+    Make breakpoint pending on future shared library load? (y or [n]) y
+    Breakpoint 1 (btrfs_init_sysfs) pending.
+
+- Continue the target::
+
+    (gdb) c
+
+- Load the module on the target and watch the symbols being loaded as well as
+  the breakpoint hit::
+
+    loading @0xffffffffa0034000: /home/user/linux/build/lib/libcrc32c.ko
+    loading @0xffffffffa0050000: /home/user/linux/build/lib/lzo/lzo_compress.ko
+    loading @0xffffffffa006e000: /home/user/linux/build/lib/zlib_deflate/zlib_deflate.ko
+    loading @0xffffffffa01b1000: /home/user/linux/build/fs/btrfs/btrfs.ko
+
+    Breakpoint 1, btrfs_init_sysfs () at /home/user/linux/fs/btrfs/sysfs.c:36
+    36              btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
+
+- Dump the log buffer of the target kernel::
+
+    (gdb) lx-dmesg
+    [     0.000000] Initializing cgroup subsys cpuset
+    [     0.000000] Initializing cgroup subsys cpu
+    [     0.000000] Linux version 3.8.0-rc4-dbg+ (...
+    [     0.000000] Command line: root=/dev/sda2 resume=/dev/sda1 vga=0x314
+    [     0.000000] e820: BIOS-provided physical RAM map:
+    [     0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
+    [     0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
+    ....
+
+- Examine fields of the current task struct::
+
+    (gdb) p $lx_current().pid
+    $1 = 4998
+    (gdb) p $lx_current().comm
+    $2 = "modprobe\000\000\000\000\000\000\000"
+
+- Make use of the per-cpu function for the current or a specified CPU::
+
+    (gdb) p $lx_per_cpu("runqueues").nr_running
+    $3 = 1
+    (gdb) p $lx_per_cpu("runqueues", 2).nr_running
+    $4 = 0
+
+- Dig into hrtimers using the container_of helper::
+
+    (gdb) set $next = $lx_per_cpu("hrtimer_bases").clock_base[0].active.next
+    (gdb) p *$container_of($next, "struct hrtimer", "node")
+    $5 = {
+      node = {
+        node = {
+          __rb_parent_color = 18446612133355256072,
+          rb_right = 0x0 <irq_stack_union>,
+          rb_left = 0x0 <irq_stack_union>
+        },
+        expires = {
+          tv64 = 1835268000000
+        }
+      },
+      _softexpires = {
+        tv64 = 1835268000000
+      },
+      function = 0xffffffff81078232 <tick_sched_timer>,
+      base = 0xffff88003fd0d6f0,
+      state = 1,
+      start_pid = 0,
+      start_site = 0xffffffff81055c1f <hrtimer_start_range_ns+20>,
+      start_comm = "swapper/2\000\000\000\000\000\000"
+    }
+
+
+List of commands and functions
+------------------------------
+
+The number of commands and convenience functions may evolve over the time,
+this is just a snapshot of the initial version::
+
+ (gdb) apropos lx
+ function lx_current -- Return current task
+ function lx_module -- Find module by name and return the module variable
+ function lx_per_cpu -- Return per-cpu variable
+ function lx_task_by_pid -- Find Linux task by PID and return the task_struct variable
+ function lx_thread_info -- Calculate Linux thread_info from task variable
+ lx-dmesg -- Print Linux kernel log buffer
+ lx-lsmod -- List currently loaded modules
+ lx-symbols -- (Re-)load symbols of Linux kernel and currently loaded modules
+
+Detailed help can be obtained via "help <command-name>" for commands and "help
+function <function-name>" for convenience functions.
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
new file mode 100644
index 000000000000..f7a18f274357
--- /dev/null
+++ b/Documentation/dev-tools/kasan.rst
@@ -0,0 +1,173 @@
+The Kernel Address Sanitizer (KASAN)
+====================================
+
+Overview
+--------
+
+KernelAddressSANitizer (KASAN) is a dynamic memory error detector. It provides
+a fast and comprehensive solution for finding use-after-free and out-of-bounds
+bugs.
+
+KASAN uses compile-time instrumentation for checking every memory access,
+therefore you will need a GCC version 4.9.2 or later. GCC 5.0 or later is
+required for detection of out-of-bounds accesses to stack or global variables.
+
+Currently KASAN is supported only for the x86_64 and arm64 architectures.
+
+Usage
+-----
+
+To enable KASAN configure kernel with::
+
+	  CONFIG_KASAN = y
+
+and choose between CONFIG_KASAN_OUTLINE and CONFIG_KASAN_INLINE. Outline and
+inline are compiler instrumentation types. The former produces smaller binary
+the latter is 1.1 - 2 times faster. Inline instrumentation requires a GCC
+version 5.0 or later.
+
+KASAN works with both SLUB and SLAB memory allocators.
+For better bug detection and nicer reporting, enable CONFIG_STACKTRACE.
+
+To disable instrumentation for specific files or directories, add a line
+similar to the following to the respective kernel Makefile:
+
+- For a single file (e.g. main.o)::
+
+    KASAN_SANITIZE_main.o := n
+
+- For all files in one directory::
+
+    KASAN_SANITIZE := n
+
+Error reports
+~~~~~~~~~~~~~
+
+A typical out of bounds access report looks like this::
+
+    ==================================================================
+    BUG: AddressSanitizer: out of bounds access in kmalloc_oob_right+0x65/0x75 [test_kasan] at addr ffff8800693bc5d3
+    Write of size 1 by task modprobe/1689
+    =============================================================================
+    BUG kmalloc-128 (Not tainted): kasan error
+    -----------------------------------------------------------------------------
+
+    Disabling lock debugging due to kernel taint
+    INFO: Allocated in kmalloc_oob_right+0x3d/0x75 [test_kasan] age=0 cpu=0 pid=1689
+     __slab_alloc+0x4b4/0x4f0
+     kmem_cache_alloc_trace+0x10b/0x190
+     kmalloc_oob_right+0x3d/0x75 [test_kasan]
+     init_module+0x9/0x47 [test_kasan]
+     do_one_initcall+0x99/0x200
+     load_module+0x2cb3/0x3b20
+     SyS_finit_module+0x76/0x80
+     system_call_fastpath+0x12/0x17
+    INFO: Slab 0xffffea0001a4ef00 objects=17 used=7 fp=0xffff8800693bd728 flags=0x100000000004080
+    INFO: Object