[4.2.y-ckt stable] Patch "drivers/hwspinlock: use correct radix tree API" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    drivers/hwspinlock: use correct radix tree API

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From c829483aff2f33f2e9c023ec10cfd32911360342 Mon Sep 17 00:00:00 2001
From: Matthew Wilcox <willy at linux.intel.com>
Date: Fri, 20 May 2016 17:03:01 -0700
Subject: drivers/hwspinlock: use correct radix tree API

commit b76ba4af4ddd6a06f7f65769e7be1bc56556cdf5 upstream.

radix_tree_is_indirect_ptr() is an internal API.  The correct call to
use is radix_tree_deref_retry() which has the appropriate unlikely()
annotation.

Fixes: c6400ba7e13a ("drivers/hwspinlock: fix race between radix tree insertion and lookup")
Signed-off-by: Matthew Wilcox <willy at linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i at gmail.com>
Cc: Kirill Shutemov <kirill.shutemov at linux.intel.com>
Cc: Jan Kara <jack at suse.com>
Cc: Neil Brown <neilb at suse.de>
Cc: Ross Zwisler <ross.zwisler at linux.intel.com>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/hwspinlock/hwspinlock_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c
index d50c701..4074441 100644
--- a/drivers/hwspinlock/hwspinlock_core.c
+++ b/drivers/hwspinlock/hwspinlock_core.c
@@ -313,7 +313,7 @@ int of_hwspin_lock_get_id(struct device_node *np, int index)
 		hwlock = radix_tree_deref_slot(slot);
 		if (unlikely(!hwlock))
 			continue;
-		if (radix_tree_is_indirect_ptr(hwlock)) {
+		if (radix_tree_deref_retry(hwlock)) {
 			slot = radix_tree_iter_retry(&iter);
 			continue;
 		}
--
2.7.4