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, 245 insertions, 0 deletions

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
new file mode 100644
index 000000000..a9acf4575
--- /dev/null
+++ b/drivers/base/Kconfig
@@ -0,0 +1,245 @@
+# SPDX-License-Identifier: GPL-2.0
+menu "Generic Driver Options"
+
+config AUXILIARY_BUS
+	bool
+
+config UEVENT_HELPER
+	bool "Support for uevent helper"
+	help
+	  The uevent helper program is forked by the kernel for
+	  every uevent.
+	  Before the switch to the netlink-based uevent source, this was
+	  used to hook hotplug scripts into kernel device events. It
+	  usually pointed to a shell script at /sbin/hotplug.
+	  This should not be used today, because usual systems create
+	  many events at bootup or device discovery in a very short time
+	  frame. One forked process per event can create so many processes
+	  that it creates a high system load, or on smaller systems
+	  it is known to create out-of-memory situations during bootup.
+
+config UEVENT_HELPER_PATH
+	string "path to uevent helper"
+	depends on UEVENT_HELPER
+	default ""
+	help
+	  To disable user space helper program execution at by default
+	  specify an empty string here. This setting can still be altered
+	  via /proc/sys/kernel/hotplug or via /sys/kernel/uevent_helper
+	  later at runtime.
+
+config DEVTMPFS
+	bool "Maintain a devtmpfs filesystem to mount at /dev"
+	help
+	  This creates a tmpfs/ramfs filesystem instance early at bootup.
+	  In this filesystem, the kernel driver core maintains device
+	  nodes with their default names and permissions for all
+	  registered devices with an assigned major/minor number.
+	  Userspace can modify the filesystem content as needed, add
+	  symlinks, and apply needed permissions.
+	  It provides a fully functional /dev directory, where usually
+	  udev runs on top, managing permissions and adding meaningful
+	  symlinks.
+	  In very limited environments, it may provide a sufficient
+	  functional /dev without any further help. It also allows simple
+	  rescue systems, and reliably handles dynamic major/minor numbers.
+
+	  Notice: if CONFIG_TMPFS isn't enabled, the simpler ramfs
+	  file system will be used instead.
+
+config DEVTMPFS_MOUNT
+	bool "Automount devtmpfs at /dev, after the kernel mounted the rootfs"
+	depends on DEVTMPFS
+	help
+	  This will instruct the kernel to automatically mount the
+	  devtmpfs filesystem at /dev, directly after the kernel has
+	  mounted the root filesystem. The behavior can be overridden
+	  with the commandline parameter: devtmpfs.mount=0|1.
+	  This option does not affect initramfs based booting, here
+	  the devtmpfs filesystem always needs to be mounted manually
+	  after the rootfs is mounted.
+	  With this option enabled, it allows to bring up a system in
+	  rescue mode with init=/bin/sh, even when the /dev directory
+	  on the rootfs is completely empty.
+
+config DEVTMPFS_SAFE
+	bool "Use nosuid,noexec mount options on devtmpfs"
+	depends on DEVTMPFS
+	help
+	  This instructs the kernel to include the MS_NOEXEC and MS_NOSUID mount
+	  flags when mounting devtmpfs.
+
+	  Notice: If enabled, things like /dev/mem cannot be mmapped
+	  with the PROT_EXEC flag. This can break, for example, non-KMS
+	  video drivers.
+
+config DRIVER_DEFERRED_PROBE_TIMEOUT
+	int "Default value for deferred_probe_timeout"
+	default 0 if !MODULES
+	default 10 if MODULES
+	help
+	  Set the default value for the deferred_probe_timeout kernel parameter.
+	  See Documentation/admin-guide/kernel-parameters.txt for a description
+	  of the deferred_probe_timeout kernel parameter.
+
+config STANDALONE
+	bool "Select only drivers that don't need compile-time external firmware"
+	default y
+	help
+	  Select this option if you don't have magic firmware for drivers that
+	  need it.
+
+	  If unsure, say Y.
+
+config PREVENT_FIRMWARE_BUILD
+	bool "Disable drivers features which enable custom firmware building"
+	default y
+	help
+	  Say yes to disable driver features which enable building a custom
+	  driver firmware at kernel build time. These drivers do not use the
+	  kernel firmware API to load firmware (CONFIG_FW_LOADER), instead they
+	  use their own custom loading mechanism. The required firmware is
+	  usually shipped with the driver, building the driver firmware
+	  should only be needed if you have an updated firmware source.
+
+	  Firmware should not be being built as part of kernel, these days
+	  you should always prevent this and say Y here. There are only two
+	  old drivers which enable building of its firmware at kernel build
+	  time:
+
+	    o CONFIG_WANXL through CONFIG_WANXL_BUILD_FIRMWARE
+	    o CONFIG_SCSI_AIC79XX through CONFIG_AIC79XX_BUILD_FIRMWARE
+
+source "drivers/base/firmware_loader/Kconfig"
+
+config WANT_DEV_COREDUMP
+	bool
+	help
+	  Drivers should "select" this option if they desire to use the
+	  device coredump mechanism.
+
+config ALLOW_DEV_COREDUMP
+	bool "Allow device coredump" if EXPERT
+	default y
+	help
+	  This option controls if the device coredump mechanism is available or
+	  not; if disabled, the mechanism will be omitted even if drivers that
+	  can use it are enabled.
+	  Say 'N' for more sensitive systems or systems that don't want
+	  to ever access the information to not have the code, nor keep any
+	  data.
+
+	  If unsure, say Y.
+
+config DEV_COREDUMP
+	bool
+	default y if WANT_DEV_COREDUMP
+	depends on ALLOW_DEV_COREDUMP
+
+config DEBUG_DRIVER
+	bool "Driver Core verbose debug messages"
+	depends on DEBUG_KERNEL
+	help
+	  Say Y here if you want the Driver core to produce a bunch of
+	  debug messages to the system log. Select this if you are having a
+	  problem with the driver core and want to see more of what is
+	  going on.
+
+	  If you are unsure about this, say N here.
+
+config DEBUG_DEVRES
+	bool "Managed device resources verbose debug messages"
+	depends on DEBUG_KERNEL
+	help
+	  This option enables kernel parameter devres.log. If set to
+	  non-zero, devres debug messages are printed. Select this if
+	  you are having a problem with devres or want to debug
+	  resource management for a managed device. devres.log can be
+	  switched on and off from sysfs node.
+
+	  If you are unsure about this, Say N here.
+
+config DEBUG_TEST_DRIVER_REMOVE
+	bool "Test driver remove calls during probe (UNSTABLE)"
+	depends on DEBUG_KERNEL
+	help
+	  Say Y here if you want the Driver core to test driver remove functions
+	  by calling probe, remove, probe. This tests the remove path without
+	  having to unbind the driver or unload the driver module.
+
+	  This option is expected to find errors and may render your system
+	  unusable. You should say N here unless you are explicitly looking to
+	  test this functionality.
+
+config PM_QOS_KUNIT_TEST
+	bool "KUnit Test for PM QoS features" if !KUNIT_ALL_TESTS
+	depends on KUNIT=y
+	default KUNIT_ALL_TESTS
+
+config PM_RUNTIME_KUNIT_TEST
+	tristate "KUnit Tests for runtime PM" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	depends on PM
+	default KUNIT_ALL_TESTS
+
+config HMEM_REPORTING
+	bool
+	default n
+	depends on NUMA
+	help
+	  Enable reporting for heterogeneous memory access attributes under
+	  their non-uniform memory nodes.
+
+source "drivers/base/test/Kconfig"
+
+config SYS_HYPERVISOR
+	bool
+	default n
+
+config GENERIC_CPU_DEVICES
+	bool
+	default n
+
+config GENERIC_CPU_AUTOPROBE
+	bool
+
+config GENERIC_CPU_VULNERABILITIES
+	bool
+
+config SOC_BUS
+	bool
+	select GLOB
+
+source "drivers/base/regmap/Kconfig"
+
+config DMA_SHARED_BUFFER
+	bool
+	default n
+	select IRQ_WORK
+	help
+	  This option enables the framework for buffer-sharing between
+	  multiple drivers. A buffer is associated with a file using driver
+	  APIs extension; the file's descriptor can then be passed on to other
+	  driver.
+
+config GENERIC_ARCH_TOPOLOGY
+	bool
+	help
+	  Enable support for architectures common topology code: e.g., parsing
+	  CPU capacity information from DT, usage of such information for
+	  appropriate scaling, sysfs interface for reading capacity values at
+	  runtime.
+
+config FW_DEVLINK_SYNC_STATE_TIMEOUT
+	bool "sync_state() behavior defaults to timeout instead of strict"
+	help
+	  This is build time equivalent of adding kernel command line parameter
+	  "fw_devlink.sync_state=timeout". Give up waiting on consumers and
+	  call sync_state() on any devices that haven't yet received their
+	  sync_state() calls after deferred_probe_timeout has expired or by
+	  late_initcall() if !CONFIG_MODULES. You should almost always want to
+	  select N here unless you have already successfully tested with the
+	  command line option on every system/board your kernel is expected to
+	  work on.
+
+endmenu