[PATCH 4.18 142/171] mm/swapfile.c: use kvzalloc for swap_info_struct allocation

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Vasily Averin <vvs@xxxxxxxxxxxxx>

commit 873d7bcfd066663e3e50113dc4a0de19289b6354 upstream.

Commit a2468cc9bfdf ("swap: choose swap device according to numa node")
changed 'avail_lists' field of 'struct swap_info_struct' to an array.
In popular linux distros it increased size of swap_info_struct up to 40
Kbytes and now swap_info_struct allocation requires order-4 page.
Switch to kvzmalloc allows to avoid unexpected allocation failures.

Link: http://lkml.kernel.org/r/fc23172d-3c75-21e2-d551-8b1808cbe593@xxxxxxxxxxxxx
Fixes: a2468cc9bfdf ("swap: choose swap device according to numa node")
Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
Acked-by: Aaron Lu <aaron.lu@xxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 mm/swapfile.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2837,7 +2837,7 @@ static struct swap_info_struct *alloc_sw
 	unsigned int type;
 	int i;
 
-	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	p = kvzalloc(sizeof(*p), GFP_KERNEL);
 	if (!p)
 		return ERR_PTR(-ENOMEM);
 
@@ -2848,7 +2848,7 @@ static struct swap_info_struct *alloc_sw
 	}
 	if (type >= MAX_SWAPFILES) {
 		spin_unlock(&swap_lock);
-		kfree(p);
+		kvfree(p);
 		return ERR_PTR(-EPERM);
 	}
 	if (type >= nr_swapfiles) {
@@ -2862,7 +2862,7 @@ static struct swap_info_struct *alloc_sw
 		smp_wmb();
 		nr_swapfiles++;
 	} else {
-		kfree(p);
+		kvfree(p);
 		p = swap_info[type];
 		/*
 		 * Do not memset this entry: a racing procfs swap_next()