From 5abfd909072336c543d82e182843e080b2009586 Mon Sep 17 00:00:00 2001
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Date: Mon, 29 Nov 2021 16:28:47 +0800
Subject: [PATCH] mm: Ignore madvise(MADV_MERGEABLE) request for VM_CDM marked
 VMAs

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4JMLR
CVE: NA
-------------------

VMA containing CDM memory should be excluded from KSM merging. This change
makes madvise(MADV_MERGEABLE) request on target VMA to be ignored.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Lijun Fang <fanglijun3@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
---
 mm/ksm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mm/ksm.c b/mm/ksm.c
index 25b8362a4f89..582c02058baf 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -38,6 +38,7 @@
 #include <linux/freezer.h>
 #include <linux/oom.h>
 #include <linux/numa.h>
+#include <linux/mempolicy.h>
 
 #include <asm/tlbflush.h>
 #include "internal.h"
@@ -2454,6 +2455,11 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start,
 		if (vma_is_dax(vma))
 			return 0;
 
+#ifdef CONFIG_COHERENT_DEVICE
+		if (is_cdm_vma(vma))
+			return 0;
+#endif
+
 #ifdef VM_SAO
 		if (*vm_flags & VM_SAO)
 			return 0;
-- 
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