Patch "kernel/extable.c: mark core_kernel_text notrace" has been added to the 4.12-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    kernel/extable.c: mark core_kernel_text notrace

to the 4.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kernel-extable.c-mark-core_kernel_text-notrace.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c0d80ddab89916273cb97114889d3f337bc370ae Mon Sep 17 00:00:00 2001
From: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Date: Thu, 6 Jul 2017 15:35:31 -0700
Subject: kernel/extable.c: mark core_kernel_text notrace

From: Marcin Nowakowski <marcin.nowakowski@imgtec.com>

commit c0d80ddab89916273cb97114889d3f337bc370ae upstream.

core_kernel_text is used by MIPS in its function graph trace processing,
so having this method traced leads to an infinite set of recursive calls
such as:

  Call Trace:
     ftrace_return_to_handler+0x50/0x128
     core_kernel_text+0x10/0x1b8
     prepare_ftrace_return+0x6c/0x114
     ftrace_graph_caller+0x20/0x44
     return_to_handler+0x10/0x30
     return_to_handler+0x0/0x30
     return_to_handler+0x0/0x30
     ftrace_ops_no_ops+0x114/0x1bc
     core_kernel_text+0x10/0x1b8
     core_kernel_text+0x10/0x1b8
     core_kernel_text+0x10/0x1b8
     ftrace_ops_no_ops+0x114/0x1bc
     core_kernel_text+0x10/0x1b8
     prepare_ftrace_return+0x6c/0x114
     ftrace_graph_caller+0x20/0x44
     (...)

Mark the function notrace to avoid it being traced.

Link: http://lkml.kernel.org/r/1498028607-6765-1-git-send-email-marcin.nowakowski@imgtec.com
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Meyer <thomas@m3y3r.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/extable.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -69,7 +69,7 @@ static inline int init_kernel_text(unsig
 	return 0;
 }
 
-int core_kernel_text(unsigned long addr)
+int notrace core_kernel_text(unsigned long addr)
 {
 	if (addr >= (unsigned long)_stext &&
 	    addr < (unsigned long)_etext)


Patches currently in stable-queue which might be from marcin.nowakowski@imgtec.com are

queue-4.12/kernel-extable.c-mark-core_kernel_text-notrace.patch