Patch "MIPS: ralink: Remove ralink_halt()" has been added to the 4.4-stable tree

Patch "MIPS: ralink: Remove ralink_halt()" 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

    MIPS: ralink: Remove ralink_halt()

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:
     mips-ralink-remove-ralink_halt.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 891731f6a5dbe508d12443175a7e166a2fba616a Mon Sep 17 00:00:00 2001
From: NeilBrown <neil@brown.name>
Date: Tue, 20 Mar 2018 19:29:51 +1100
Subject: MIPS: ralink: Remove ralink_halt()

From: NeilBrown <neil@brown.name>

commit 891731f6a5dbe508d12443175a7e166a2fba616a upstream.

ralink_halt() does nothing that machine_halt() doesn't already do, so it
adds no value.

It actually causes incorrect behaviour due to the "unreachable()" at the
end. This tells the compiler that the end of the function will never be
reached, which isn't true. The compiler responds by not adding a
'return' instruction, so control simply moves on to whatever bytes come
afterwards in memory. In my tested, that was the ralink_restart()
function. This means that an attempt to 'halt' the machine would
actually cause a reboot.

So remove ralink_halt() so that a 'halt' really does halt.

Fixes: c06e836ada59 ("MIPS: ralink: adds reset code")
Signed-off-by: NeilBrown <neil@brown.name>
Cc: John Crispin <john@phrozen.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.9+
Patchwork: https://patchwork.linux-mips.org/patch/18851/
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/ralink/reset.c |    7 -------
 1 file changed, 7 deletions(-)

--- a/arch/mips/ralink/reset.c
+++ b/arch/mips/ralink/reset.c
@@ -96,16 +96,9 @@ static void ralink_restart(char *command
 	unreachable();
 }
 
-static void ralink_halt(void)
-{
-	local_irq_disable();
-	unreachable();
-}
-
 static int __init mips_reboot_setup(void)
 {
 	_machine_restart = ralink_restart;
-	_machine_halt = ralink_halt;
 
 	return 0;
 }


Patches currently in stable-queue which might be from neil@brown.name are

queue-4.4/mips-ralink-remove-ralink_halt.patch