[PATCH 0/3] ftrace, orc, x86, tracing: Fix stack traces again

From: Steven Rostedt
Date: Tue Jan 23 2018 - 13:37:41 EST



With the new ORC unwinder, ftrace stack tracing became disfunctional.

One was that ORC didn't know how to handle the ftrace callbacks in
general (which Josh fixed). The other was that ORC would just bail
if it hit a dynamically allocated trampoline. I added a check to
the ORC unwinder to see if the trampoline belonged to ftrace, and
if it did, use the orc entry of the static trampoline that was used
to create the dynamic one (it would be identical).

Finally, I noticed that the skip values of the stack tracing is out
of whack. I went through and fixed them.

Anyone have any issues with these patches? I'm starting my tests on
them now and if all goes well, I plan on pushing them to Linus
hopefully tonight.

Thanks!

-- Steve


Josh Poimboeuf (1):
x86/ftrace: Fix ORC unwinding from ftrace handlers

Steven Rostedt (VMware) (2):
ftrace, orc, x86: Handle ftrace dynamically allocated trampolines
tracing: Update stack trace skipping for ORC unwinder

----
arch/x86/kernel/Makefile | 5 +++-
arch/x86/kernel/ftrace_64.S | 24 +++++++++++-------
arch/x86/kernel/unwind_orc.c | 48 +++++++++++++++++++++++++++++++++++-
include/linux/ftrace.h | 2 ++
kernel/trace/ftrace.c | 26 +++++++++++---------
kernel/trace/trace.c | 34 ++++++++++++++-----------
kernel/trace/trace_events_trigger.c | 13 ++++++++--
kernel/trace/trace_functions.c | 49 +++++++++++++++++++++++++++----------
8 files changed, 150 insertions(+), 51 deletions(-)