• Linus Torvalds's avatar
    Merge tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · 452938cb
    Linus Torvalds authored
    Pull tracing fixes from Steven Rostedt:
     "Masami found an off by one bug in the code that keeps "notrace"
      functions from being traced by kprobes. During my testing, I found
      that there's places that we may want to add kprobes to notrace, thus
      we may end up changing this code before 4.19 is released.
    
      The history behind this change is that we found that adding kprobes to
      various notrace functions caused the kernel to crashed. We took the
      safe route and decided not to allow kprobes to trace any notrace
      function.
    
      But because notrace is added to functions that just cause weird side
      effects to the function tracer, but are still safe, preventing kprobes
      for all notrace functios may be too much of a big hammer.
    
      One such place is __schedule() is marked notrace, to keep function
      tracer from doing strange recursive loops when it gets traced with
      NEED_RESCHED set. With this change, one can not add kprobes to the
      scheduler.
    
      Masami also added code to use gcov on ftrace"
    
    * tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
      tracing/kprobes: Fix to check notrace function with correct range
      tracing: Allow gcov profiling on only ftrace subsystem
    452938cb
trace_kprobe.c 41.7 KB