From 4149bf498a3490a8ab506109e3893087f35fd23f Mon Sep 17 00:00:00 2001
From: Debabrata Banerjee <dbanerje@akamai.com>
Date: Wed, 15 Mar 2017 21:01:31 -0400
Subject: [PATCH] Correct signed operation

Could return the wrong pages value

AKAMAI: zfs: CR 3695072
Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed-by: Richard Yao <ryao@gentoo.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com>
Issue #6035
---
 module/zfs/arc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index efac973bae..ce92460616 100644
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -4430,7 +4430,8 @@ __arc_shrinker_func(struct shrinker *shrink, struct shrink_control *sc)
 		if (current_is_kswapd())
 			arc_kmem_reap_now();
 #ifdef HAVE_SPLIT_SHRINKER_CALLBACK
-		pages = MAX(pages - btop(arc_evictable_memory()), 0);
+		pages = MAX((int64_t)pages -
+		    (int64_t)btop(arc_evictable_memory()), 0);
 #else
 		pages = btop(arc_evictable_memory());
 #endif
@@ -4438,7 +4439,6 @@ __arc_shrinker_func(struct shrinker *shrink, struct shrink_control *sc)
 		 * We've shrunk what we can, wake up threads.
 		 */
 		cv_broadcast(&arc_reclaim_waiters_cv);
-
 	} else
 		pages = SHRINK_STOP;