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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 v4 35/35] mm: Avoid rewalk in mmap_region
Date:   Thu, 18 May 2023 10:55:44 -0400
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If the iterator has moved to the previous entry, then step forward one
range, back to the gap.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 mm/mmap.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/mmap.c b/mm/mmap.c
index 1602c854133a..71733953ff83 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2636,6 +2636,9 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 	}
 
 cannot_expand:
+	if (prev)
+		vma_iter_next_range(&vmi);
+
 	/*
 	 * Determine the object being mapped and call the appropriate
 	 * specific mapper. the address has already been validated, but
-- 
2.39.2