mbox series

[for-linus,0/2] tracing: Minor updates for 6.4

Message ID 20230503231446.234385640@goodmis.org
Headers
Series tracing: Minor updates for 6.4 |

Message

Steven Rostedt May 3, 2023, 11:14 p.m. UTC 
  Minor updates:

- Make buffer_percent read/write. The buffer_percent file is how users can
  state how long to block on the tracing buffer depending on how much
  is in the buffer. When it hits the "buffer_percent" it will wake the
  task waiting on the buffer. For some reason it was set to read-only.
  This was not noticed because testing was done as root without SELinux,
  but with SELinux it will prevent even root to write to it without having
  CAP_DAC_OVERRIDE.

- The "touched_functions" was added this merge window, but one of the
  reasons for adding it was not implemented. That was to show what functions
  were not only touched, but had either a direct trampoline attached to
  it, or a kprobe or live kernel patching that can "hijack" the function
  to can a different function. The point is to know if there's functions
  in the kernel that may not be behaving as kernel code shows. This can
  be used for debugging. TODO: Add this information to kernel oops too.

Ondrej Mosnacek (1):
      tracing: Fix permissions for the buffer_percent file

Steven Rostedt (Google) (1):
      ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attached

----
 Documentation/trace/ftrace.rst | 25 +++++++++++++++++++++++++
 include/linux/ftrace.h         |  4 +++-
 kernel/trace/ftrace.c          | 12 +++++++++---
 kernel/trace/trace.c           |  2 +-
 4 files changed, 38 insertions(+), 5 deletions(-)