From b920e0e9af880abfdbd48c1e456f30383388c21f Mon Sep 17 00:00:00 2001
From: Wei Yang <richardw.yang@linux.intel.com>
Date: Sat, 30 Nov 2019 17:50:37 -0800
Subject: [PATCH] mm/mmap.c: remove a never-triggered warning in __vma_adjust()

References: bnc#1155780 (VM/FS functional and performance backports)
Patch-mainline: v5.5-rc1
Git-commit: 408a60eddd206134fd306dfbc53bbde093b8deb0

The upper level of "if" makes sure (end >= next->vm_end), which means
there are only two possibilities:

   1) end == next->vm_end
   2) end > next->vm_end

remove_next is assigned to be (1 + end > next->vm_end).  This means if
remove_next is 1, end must equal to next->vm_end.

The VM_WARN_ON will never trigger.

Link: http://lkml.kernel.org/r/20190912063126.13250-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 mm/mmap.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 7e8c3e8ae75f..fc6c776eb9d2 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -760,8 +760,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
 				remove_next = 1 + (end > next->vm_end);
 				VM_WARN_ON(remove_next == 2 &&
 					   end != next->vm_next->vm_end);
-				VM_WARN_ON(remove_next == 1 &&
-					   end != next->vm_end);
 				/* trim end to next, for case 6 first pass */
 				end = next->vm_end;
 			}