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Subject: [PATCH v3 11/14] mm/migrate_device: Support COW PTE
Date:   Tue, 20 Dec 2022 15:27:40 +0800
Message-Id: <20221220072743.3039060-12-shiyn.lin@gmail.com>
In-Reply-To: <20221220072743.3039060-1-shiyn.lin@gmail.com>
References: <20221220072743.3039060-1-shiyn.lin@gmail.com>
MIME-Version: 1.0
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Break COW PTE before collecting the pages in COW-ed PTE.

Signed-off-by: Chih-En Lin <shiyn.lin@gmail.com>
---
 mm/migrate_device.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/migrate_device.c b/mm/migrate_device.c
index 721b2365dbca9..f6d67bd9629f5 100644
--- a/mm/migrate_device.c
+++ b/mm/migrate_device.c
@@ -106,6 +106,8 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
 		}
 	}
 
+	if (!break_cow_pte_range(vma, pmdp, start, end))
+		return migrate_vma_collect_skip(start, end, walk);
 	if (unlikely(pmd_bad(*pmdp)))
 		return migrate_vma_collect_skip(start, end, walk);
 
-- 
2.37.3