Patch "jump_labels: API for flushing deferred jump label updates" has been added to the 4.9-stable tree

Patch "jump_labels: API for flushing deferred jump label updates" has been added to the 4.9-stable tree

[gregkh]

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

    jump_labels: API for flushing deferred jump label updates

to the 4.9-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:
     jump_labels-api-for-flushing-deferred-jump-label-updates.patch
and it can be found in the queue-4.9 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 b6416e61012429e0277bd15a229222fd17afc1c1 Mon Sep 17 00:00:00 2001
From: David Matlack <dmatlack@google.com>
Date: Fri, 16 Dec 2016 14:30:35 -0800
Subject: jump_labels: API for flushing deferred jump label updates

From: David Matlack <dmatlack@google.com>

commit b6416e61012429e0277bd15a229222fd17afc1c1 upstream.

Modules that use static_key_deferred need a way to synchronize with
any delayed work that is still pending when the module is unloaded.
Introduce static_key_deferred_flush() which flushes any pending
jump label updates.

Signed-off-by: David Matlack <dmatlack@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 include/linux/jump_label_ratelimit.h |    5 +++++
 kernel/jump_label.c                  |    7 +++++++
 2 files changed, 12 insertions(+)

--- a/include/linux/jump_label_ratelimit.h
+++ b/include/linux/jump_label_ratelimit.h
@@ -14,6 +14,7 @@ struct static_key_deferred {
 
 #ifdef HAVE_JUMP_LABEL
 extern void static_key_slow_dec_deferred(struct static_key_deferred *key);
+extern void static_key_deferred_flush(struct static_key_deferred *key);
 extern void
 jump_label_rate_limit(struct static_key_deferred *key, unsigned long rl);
 
@@ -26,6 +27,10 @@ static inline void static_key_slow_dec_d
 	STATIC_KEY_CHECK_USE();
 	static_key_slow_dec(&key->key);
 }
+static inline void static_key_deferred_flush(struct static_key_deferred *key)
+{
+	STATIC_KEY_CHECK_USE();
+}
 static inline void
 jump_label_rate_limit(struct static_key_deferred *key,
 		unsigned long rl)
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -182,6 +182,13 @@ void static_key_slow_dec_deferred(struct
 }
 EXPORT_SYMBOL_GPL(static_key_slow_dec_deferred);
 
+void static_key_deferred_flush(struct static_key_deferred *key)
+{
+	STATIC_KEY_CHECK_USE();
+	flush_delayed_work(&key->work);
+}
+EXPORT_SYMBOL_GPL(static_key_deferred_flush);
+
 void jump_label_rate_limit(struct static_key_deferred *key,
 		unsigned long rl)
 {


Patches currently in stable-queue which might be from dmatlack@google.com are

queue-4.9/kvm-x86-flush-pending-lapic-jump-label-updates-on-module-unload.patch
queue-4.9/jump_labels-api-for-flushing-deferred-jump-label-updates.patch