From fe079a5e102cc59b6c2b66a41e39c624ce284519 Mon Sep 17 00:00:00 2001
From: Alexey Dobriyan <adobriyan@gmail.com>
Date: Tue, 10 Apr 2018 16:32:05 -0700
Subject: [PATCH] proc: do mmput ASAP for /proc/*/map_files

mm_struct is not needed while printing as all the data was already
extracted.

Link: http://lkml.kernel.org/r/20180309223120.GC3843@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 fs/proc/base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index d413a138dc30..eafa39a3a88c 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2211,6 +2211,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
 		}
 	}
 	up_read(&mm->mmap_sem);
+	mmput(mm);
 
 	for (i = 0; i < nr_files; i++) {
 		char buf[4 * sizeof(long) + 2];	/* max: %lx-%lx\0 */
@@ -2228,7 +2229,6 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
 	}
 	if (fa)
 		flex_array_free(fa);
-	mmput(mm);
 
 out_put_task:
 	put_task_struct(task);