Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 145 insertions, 0 deletions

diff --git a/lib/kunit/Kconfig b/lib/kunit/Kconfig
new file mode 100644
index 000000000..94ff8e408
--- /dev/null
+++ b/lib/kunit/Kconfig
@@ -0,0 +1,145 @@
+#
+# KUnit base configuration
+#
+
+menuconfig KUNIT
+	tristate "KUnit - Enable support for unit tests"
+	select GLOB
+	help
+	  Enables support for kernel unit tests (KUnit), a lightweight unit
+	  testing and mocking framework for the Linux kernel. These tests are
+	  able to be run locally on a developer's workstation without a VM or
+	  special hardware when using UML. Can also be used on most other
+	  architectures. For more information, please see
+	  Documentation/dev-tools/kunit/.
+
+if KUNIT
+
+config KUNIT_DEBUGFS
+	bool "KUnit - Enable /sys/kernel/debug/kunit debugfs representation"
+	depends on DEBUG_FS
+	default y
+	help
+	  Enable debugfs representation for kunit.  Currently this consists
+	  of /sys/kernel/debug/kunit/<test_suite>/results files for each
+	  test suite, which allow users to see results of the last test suite
+	  run that occurred.
+
+config KUNIT_FAULT_TEST
+	bool "Enable KUnit tests which print BUG stacktraces"
+	depends on KUNIT_TEST
+	depends on !UML
+	default !PANIC_ON_OOPS
+	help
+	  Enables fault handling tests for the KUnit framework. These tests may
+	  trigger a kernel BUG(), and the associated stack trace, even when they
+	  pass. If this conflicts with your test infrastrcture (or is confusing
+	  or annoying), they can be disabled by setting this to N.
+
+config KUNIT_TEST
+	tristate "KUnit test for KUnit" if !KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS
+	help
+	  Enables the unit tests for the KUnit test framework. These tests test
+	  the KUnit test framework itself; the tests are both written using
+	  KUnit and test KUnit. This option should only be enabled for testing
+	  purposes by developers interested in testing that KUnit works as
+	  expected.
+
+config KUNIT_EXAMPLE_TEST
+	tristate "Example test for KUnit" if !KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS
+	help
+	  Enables an example unit test that illustrates some of the basic
+	  features of KUnit. This test only exists to help new users understand
+	  what KUnit is and how it is used. Please refer to the example test
+	  itself, lib/kunit/example-test.c, for more information. This option
+	  is intended for curious hackers who would like to understand how to
+	  use KUnit for kernel development.
+
+config KUNIT_ALL_TESTS
+	tristate "All KUnit tests with satisfied dependencies"
+	help
+	  Enables all KUnit tests, if they can be enabled.
+	  KUnit tests run during boot and output the results to the debug log
+	  in TAP format (http://testanything.org/). Only useful for kernel devs
+	  running the KUnit test harness, and not intended for inclusion into a
+	  production build.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+	  If unsure, say N.
+
+config KUNIT_DEFAULT_ENABLED
+	bool "Default value of kunit.enable"
+	default y
+	help
+	  Sets the default value of kunit.enable. If set to N then KUnit
+	  tests will not execute unless kunit.enable=1 is passed to the
+	  kernel command line.
+
+	  In most cases this should be left as Y. Only if additional opt-in
+	  behavior is needed should this be set to N.
+
+config KUNIT_AUTORUN_ENABLED
+	bool "Default value of kunit.autorun"
+	default y
+	help
+	  Sets the default value of kunit.autorun. If set to N then KUnit
+	  tests will not run after initialization unless kunit.autorun=1 is
+	  passed to the kernel command line. The test can still be run manually
+	  via debugfs interface.
+
+	  In most cases this should be left as Y. Only if additional opt-in
+	  behavior is needed should this be set to N.
+
+config KUNIT_DEFAULT_FILTER_GLOB
+	string "Default value of the filter_glob module parameter"
+	help
+	  Sets the default value of kunit.filter_glob. If set to a non-empty
+	  string only matching tests are executed.
+
+	  If unsure, leave empty so all tests are executed.
+
+config KUNIT_DEFAULT_FILTER
+	string "Default value of the filter module parameter"
+	help
+	  Sets the default value of kunit.filter. If set to a non-empty
+	  string only matching tests are executed.
+
+	  If unsure, leave empty so all tests are executed.
+
+config KUNIT_DEFAULT_FILTER_ACTION
+	string "Default value of the filter_action module parameter"
+	help
+	  Sets the default value of kunit.filter_action. If set to a non-empty
+	  string only matching tests are executed.
+
+	  If unsure, leave empty so all tests are executed.
+
+config KUNIT_DEFAULT_TIMEOUT
+	int "Default value of the timeout module parameter"
+	default 300
+	help
+	  Sets the default timeout, in seconds, for Kunit test cases. This value
+	  is further multiplied by a factor determined by the assigned speed
+	  setting: 1x for `DEFAULT`, 3x for `KUNIT_SPEED_SLOW`, and 12x for
+	  `KUNIT_SPEED_VERY_SLOW`. This allows slower tests on slower machines
+	  sufficient time to complete.
+
+	  If unsure, the default timeout of 300 seconds is suitable for most
+	  cases.
+
+config KUNIT_UML_PCI
+	bool "KUnit UML PCI Support"
+	depends on UML
+	select UML_PCI
+	help
+	  Enables the PCI subsystem on UML for use by KUnit tests.
+	  Some KUnit tests require the PCI core which is not enabled by
+	  default on UML.
+
+	  If unsure, say N.
+
+endif # KUNIT