Patch "powerpc/xmon: Check before calling xive functions" has been added to the 4.14-stable tree

Patch "powerpc/xmon: Check before calling xive functions" has been added to the 4.14-stable tree

[gregkh]

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

    powerpc/xmon: Check before calling xive functions

to the 4.14-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:
     powerpc-xmon-check-before-calling-xive-functions.patch
and it can be found in the queue-4.14 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 foo@baz Mon Dec 18 13:28:59 CET 2017
From: Breno Leitao <leitao@debian.org>
Date: Tue, 17 Oct 2017 16:20:18 -0200
Subject: powerpc/xmon: Check before calling xive functions

From: Breno Leitao <leitao@debian.org>


[ Upstream commit 402e172a2ce76210f2fe921cf419d12103851344 ]

Currently xmon could call XIVE functions from OPAL even if the XIVE is
disabled or does not exist in the system, as in POWER8 machines. This
causes the following exception:

 1:mon> dx
 cpu 0x1: Vector: 700 (Program Check) at [c000000423c93450]
     pc: c00000000009cfa4: opal_xive_dump+0x50/0x68
     lr: c0000000000997b8: opal_return+0x0/0x50

This patch simply checks if XIVE is enabled before calling XIVE
functions.

Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Suggested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/xmon/xmon.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2475,6 +2475,11 @@ static void dump_xives(void)
 	unsigned long num;
 	int c;
 
+	if (!xive_enabled()) {
+		printf("Xive disabled on this system\n");
+		return;
+	}
+
 	c = inchar();
 	if (c == 'a') {
 		dump_all_xives();


Patches currently in stable-queue which might be from leitao@debian.org are

queue-4.14/powerpc-xmon-check-before-calling-xive-functions.patch