Patch "arc: unwind: warn only once if DW2_UNWIND is disabled" has been added to the 4.4-stable tree

Patch "arc: unwind: warn only once if DW2_UNWIND is disabled" has been added to the 4.4-stable tree

[gregkh]

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

    arc: unwind: warn only once if DW2_UNWIND is disabled

to the 4.4-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:
     arc-unwind-warn-only-once-if-dw2_unwind-is-disabled.patch
and it can be found in the queue-4.4 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 9bd54517ee86cb164c734f72ea95aeba4804f10b Mon Sep 17 00:00:00 2001
From: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Date: Thu, 23 Jun 2016 11:00:39 +0300
Subject: arc: unwind: warn only once if DW2_UNWIND is disabled

From: Alexey Brodkin <Alexey.Brodkin@synopsys.com>

commit 9bd54517ee86cb164c734f72ea95aeba4804f10b upstream.

If CONFIG_ARC_DW2_UNWIND is disabled every time arc_unwind_core()
gets called following message gets printed in debug console:
----------------->8---------------
CONFIG_ARC_DW2_UNWIND needs to be enabled
----------------->8---------------

That message makes sense if user indeed wants to see a backtrace or
get nice function call-graphs in perf but what if user disabled
unwinder for the purpose? Why pollute his debug console?

So instead we'll warn user about possibly missing feature once and
let him decide if that was what he or she really wanted.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/arch/arc/kernel/stacktrace.c
+++ b/arch/arc/kernel/stacktrace.c
@@ -142,7 +142,7 @@ arc_unwind_core(struct task_struct *tsk,
 	 * prelogue is setup (callee regs saved and then fp set and not other
 	 * way around
 	 */
-	pr_warn("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");
+	pr_warn_once("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");
 	return 0;
 
 #endif


Patches currently in stable-queue which might be from Alexey.Brodkin@synopsys.com are

queue-4.4/arc-unwind-warn-only-once-if-dw2_unwind-is-disabled.patch