From cb9d7fd51d9fbb329d182423bd7b92d0f8cb0e01 Mon Sep 17 00:00:00 2001
From: Vincent Whitchurch <vincent.whitchurch@axis.com>
Date: Tue, 21 Aug 2018 17:25:07 +0200
Subject: watchdog: Mark watchdog touch functions as notrace

Some architectures need to use stop_machine() to patch functions for
ftrace, and the assumption is that the stopped CPUs do not make function
calls to traceable functions when they are in the stopped state.

Commit ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after
MULTI_STOP_PREPARE") added calls to the watchdog touch functions from
the stopped CPUs and those functions lack notrace annotations.  This
leads to crashes when enabling/disabling ftrace on ARM kernels built
with the Thumb-2 instruction set.

Fix it by adding the necessary notrace annotations.

Fixes: ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: oleg@redhat.com
Cc: tj@kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180821152507.18313-1-vincent.whitchurch@axis.com
---
 kernel/watchdog.c     | 4 ++--
 kernel/watchdog_hld.c | 2 +-
 kernel/workqueue.c    | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

(limited to 'kernel')

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 5470dce212c0..977918d5d350 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -261,7 +261,7 @@ static void __touch_watchdog(void)
  * entering idle state.  This should only be used for scheduler events.
  * Use touch_softlockup_watchdog() for everything else.
  */
-void touch_softlockup_watchdog_sched(void)
+notrace void touch_softlockup_watchdog_sched(void)
 {
 	/*
 	 * Preemption can be enabled.  It doesn't matter which CPU's timestamp
@@ -270,7 +270,7 @@ void touch_softlockup_watchdog_sched(void)
 	raw_cpu_write(watchdog_touch_ts, 0);
 }
 
-void touch_softlockup_watchdog(void)
+notrace void touch_softlockup_watchdog(void)
 {
 	touch_softlockup_watchdog_sched();
 	wq_watchdog_touch(raw_smp_processor_id());
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index 1f7020d65d0a..71381168dede 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -29,7 +29,7 @@ static struct cpumask dead_events_mask;
 static unsigned long hardlockup_allcpu_dumped;
 static atomic_t watchdog_cpus = ATOMIC_INIT(0);
 
-void arch_touch_nmi_watchdog(void)
+notrace void arch_touch_nmi_watchdog(void)
 {
 	/*
 	 * Using __raw here because some code paths have
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 60e80198c3df..0280deac392e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -5574,7 +5574,7 @@ static void wq_watchdog_timer_fn(struct timer_list *unused)
 	mod_timer(&wq_watchdog_timer, jiffies + thresh);
 }
 
-void wq_watchdog_touch(int cpu)
+notrace void wq_watchdog_touch(int cpu)
 {
 	if (cpu >= 0)
 		per_cpu(wq_watchdog_touched_cpu, cpu) = jiffies;
-- 
cgit v1.2.3


From 13ba17bee18e321b073b49a88dcab10881f757da Mon Sep 17 00:00:00 2001
From: Mukesh Ojha <mojha@codeaurora.org>
Date: Fri, 24 Aug 2018 18:03:53 +0530
Subject: notifier: Remove notifier header file wherever not used

The conversion of the hotplug notifiers to a state machine left the
notifier.h includes around in some places. Remove them.

Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1535114033-4605-1-git-send-email-mojha@codeaurora.org
---
 fs/buffer.c            | 1 -
 kernel/printk/printk.c | 1 -
 lib/percpu_counter.c   | 1 -
 mm/page-writeback.c    | 1 -
 mm/page_alloc.c        | 1 -
 mm/slub.c              | 1 -
 net/core/dev.c         | 1 -
 7 files changed, 7 deletions(-)

(limited to 'kernel')

diff --git a/fs/buffer.c b/fs/buffer.c
index 4cc679d5bf58..6f1ae3ac9789 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -39,7 +39,6 @@
 #include <linux/buffer_head.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/bio.h>
-#include <linux/notifier.h>
 #include <linux/cpu.h>
 #include <linux/bitops.h>
 #include <linux/mpage.h>
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 924e37fb1620..fd6f8ed28e01 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -38,7 +38,6 @@
 #include <linux/kmsg_dump.h>
 #include <linux/syslog.h>
 #include <linux/cpu.h>
-#include <linux/notifier.h>
 #include <linux/rculist.h>
 #include <linux/poll.h>
 #include <linux/irq_work.h>
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index c72577e472f2..a66595ba5543 100644
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -4,7 +4,6 @@
  */
 
 #include <linux/percpu_counter.h>
-#include <linux/notifier.h>
 #include <linux/mutex.h>
 #include <linux/init.h>
 #include <linux/cpu.h>
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 6551d3b0dc30..84ae9bf5858a 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -27,7 +27,6 @@
 #include <linux/mpage.h>
 #include <linux/rmap.h>
 #include <linux/percpu.h>
-#include <linux/notifier.h>
 #include <linux/smp.h>
 #include <linux/sysctl.h>
 #include <linux/cpu.h>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e75865d58ba7..05e983f42316 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -32,7 +32,6 @@
 #include <linux/slab.h>
 #include <linux/ratelimit.h>
 #include <linux/oom.h>
-#include <linux/notifier.h>
 #include <linux/topology.h>
 #include <linux/sysctl.h>
 #include <linux/cpu.h>
diff --git a/mm/slub.c b/mm/slub.c
index ce2b9e5cea77..8da34a8af53d 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -19,7 +19,6 @@
 #include <linux/slab.h>
 #include "slab.h"
 #include <linux/proc_fs.h>
-#include <linux/notifier.h>
 #include <linux/seq_file.h>
 #include <linux/kasan.h>
 #include <linux/cpu.h>
diff --git a/net/core/dev.c b/net/core/dev.c
index 325fc5088370..82114e1111e6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -93,7 +93,6 @@
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
-#include <linux/notifier.h>
 #include <linux/skbuff.h>
 #include <linux/bpf.h>
 #include <linux/bpf_trace.h>
-- 
cgit v1.2.3