kprobes/x86: Remove IRQ disabling from ftrace-based/optimized kprobes
authorMasami Hiramatsu <mhiramat@kernel.org>
Tue, 19 Sep 2017 10:02:20 +0000 (19:02 +0900)
committerIngo Molnar <mingo@kernel.org>
Thu, 28 Sep 2017 07:25:50 +0000 (09:25 +0200)
commita19b2e3d783964d48d2b494439648e929bcdc976
treee9937278cf4c1555e28853edbfdb0c6de25ff68d
parent5bb4fc2d8641219732eb2bb654206775a4219aca
kprobes/x86: Remove IRQ disabling from ftrace-based/optimized kprobes

Kkprobes don't need to disable IRQs if they are called from the
ftrace/jump trampoline code, because Documentation/kprobes.txt says:

  -----
  Probe handlers are run with preemption disabled.  Depending on the
  architecture and optimization state, handlers may also run with
  interrupts disabled (e.g., kretprobe handlers and optimized kprobe
  handlers run without interrupt disabled on x86/x86-64).
  -----

So let's remove IRQ disabling from those handlers.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/150581534039.32348.11331736206004264553.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/kernel/kprobes/ftrace.c
arch/x86/kernel/kprobes/opt.c