[Devel] [PATCH RHEL7 COMMIT] mm/kasan, slub: don't disable interrupts when object leaves quarantine

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-693.1.1.vz7.37.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-693.1.1.vz7.37.4
------>
commit 337fbb1e6f518098c2cc027e992810a2cfe7dd76
Author: Andrey Ryabinin <aryabinin at virtuozzo.com>
Date:   Fri Sep 15 17:27:26 2017 +0300

    mm/kasan, slub: don't disable interrupts when object leaves quarantine
    
    SLUB doesn't require disabled interrupts to call ___cache_free().
    
    Link: http://lkml.kernel.org/r/1470062715-14077-3-git-send-email-aryabinin@virtuozzo.com
    Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
    
    Acked-by: Alexander Potapenko <glider at google.com>
    Cc: Dmitry Vyukov <dvyukov at google.com>
    Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
    
    https://jira.sw.ru/browse/PSBM-69081
    (cherry picked from commit f7376aed6c032aab820fa36806a89e16e353a0d9)
    Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
---
 mm/kasan/quarantine.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 65793f1..4852625 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -147,10 +147,14 @@ static void qlink_free(struct qlist_node *qlink, struct kmem_cache *cache)
 	struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object);
 	unsigned long flags;
 
-	local_irq_save(flags);
+	if (IS_ENABLED(CONFIG_SLAB))
+		local_irq_save(flags);
+
 	alloc_info->state = KASAN_STATE_FREE;
 	___cache_free(cache, object, _THIS_IP_);
-	local_irq_restore(flags);
+
+	if (IS_ENABLED(CONFIG_SLAB))
+		local_irq_restore(flags);
 }
 
 static void qlist_free_all(struct qlist_head *q, struct kmem_cache *cache)