[GIT PULL] probes: Fixes for v7.1

[Google]

Hi Linus,

Probes fixes for v7.1

- fprobe: Fixed several bugs, which includes followings:
  . Prevention of re-registration: Added an earlier check to reject
   re-registering an already active fprobe before its state is modified
   during the initialization phase.
  . Robustness in failure paths:
   - Ensured fprobes are correctly removed from all internal tables and
    properly RCU-freed during registration failure.
   - Modified unregister_fprobe() to proceed with unregistration even if
    temporary memory allocation fails.
  . RCU safety in module unloading: Avoided a potential "sleep in RCU"
   warning by removing a kcalloc() call in the module notifier path. This
   also tries to remove fprobe_hash_node even if memory allocation fails.
  . Type-aware unregistration: Fixed a bug where unregistering an fprobe
   did not account for different types (entry-only vs. entry-exit) at the
   same address, which previously left "junk" entries in the underlying
   ftrace/fgraph ops.
  . Unregistration of empty ftrace_ops: Avoided unneeded performance
   overhead because of making registered ftrace_ops empty (means trace
   all functions.) This counts remaining entries and unregister ftrace_ops
   when it becomes empty.

 - ftracetest: In addition to the fix, two new selftests to check above
   fixes, are included:
   . Module Unloading Test: Specifically verifies that fprobe events on
    a module are correctly cleaned up and do not trigger "trace-all"
    behavior when the module is removed.
   . Multiple Fprobe Events Test: Ensures that having multiple fprobes on
    the same function correctly manages the ftrace hash map during
    removal.


Please pull the latest probes-v7.1-2 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
probes-v7.1-2

Tag SHA1: 02ae3fda580c7421659230990bd1520a908f9808
Head SHA1: 453553e1ed53ca364454e155ba33e110d02c75cd


Masami Hiramatsu (Google) (8):
      tracing/fprobe: Reject registration of a registered fprobe before init
      tracing/fprobe: Unregister fprobe even if memory allocation fails
      tracing/fprobe: Remove fprobe from hash in failure path
      tracing/fprobe: Avoid kcalloc() in rcu_read_lock section
      tracing/fprobe: Check the same type fprobe on table as the unregistered one
      tracing/fprobe: Fix to unregister ftrace_ops if it is empty on module unloading
      selftests/ftrace: Add a testcase for fprobe events on module
      selftests/ftrace: Add a testcase for multiple fprobe events

----
 kernel/trace/fprobe.c                              | 472 ++++++++++++++-------
 .../test.d/dynevent/add_remove_fprobe_module.tc    |  87 ++++
 .../test.d/dynevent/add_remove_multiple_fprobe.tc  |  69 +++
 3 files changed, 466 insertions(+), 162 deletions(-)
 create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_module.tc
 create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_multiple_fprobe.tc
---------------------------

-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>