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From:   "Liam R. Howlett" <Liam.Howlett@oracle.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     maple-tree@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        "Liam R. Howlett" <Liam.Howlett@oracle.com>
Subject: [PATCH 05/14] mm: Remove prev check from do_vmi_align_munmap()
Date:   Wed, 31 May 2023 22:15:56 -0400
Message-Id: <20230601021605.2823123-6-Liam.Howlett@oracle.com>
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If the prev does not exist, the vma iterator will be set to MAS_NONE,
which will be treated as a MAS_START when the mas_next or mas_find is
used.  In this case, the next caller will be the vma iterator, which
uses mas_find() under the hood and will now do what the user expects.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 mm/mmap.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 8e5563668b18..fd3f505b40cc 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2402,8 +2402,6 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
 	}
 
 	prev = vma_prev(vmi);
-	if (unlikely((!prev)))
-		vma_iter_set(vmi, start);
 
 	/*
 	 * Detach a range of VMAs from the mm. Using next as a temp variable as
-- 
2.39.2