From 67334b65c3b63f41e038e7dca803917e6a414f6f Mon Sep 17 00:00:00 2001
From: Masamichi Takagi <masamichi.takagi@riken.jp>
Date: Tue, 22 Dec 2020 16:21:32 +0900
Subject: [PATCH] rus_vm_fault: vmf_insert_pfn: treat VM_FAULT_NOPAGE as
 success

vmf_insert_pfn is added with the following commit.
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1c8f422059ae5da07db7406ab916203f9417e396

Refer to the following page for the meaning of VM_FAULT_NOPAGE.
https://lwn.net/Articles/242237/

Change-Id: I2b0144a20a57c74e0e2e0d2fc24281852f49b717
---
 executer/kernel/mcctrl/syscall.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/executer/kernel/mcctrl/syscall.c b/executer/kernel/mcctrl/syscall.c
index a0a464bf..b7e974f7 100644
--- a/executer/kernel/mcctrl/syscall.c
+++ b/executer/kernel/mcctrl/syscall.c
@@ -692,14 +692,20 @@ static int rus_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 					vma->vm_start, vma->vm_end, pgsize, pix);
 			}
 		}
-		else
+		else {
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 18, 0)
 			error = vmf_insert_pfn(vma, rva+(pix*PAGE_SIZE),
 					       pfn+pix);
+			if (error == VM_FAULT_NOPAGE) {
+				dprintk("%s: vmf_insert_pfn returned %d\n",
+					__func__, error);
+				error = 0;
+			}
 #else
 			error = vm_insert_pfn(vma, rva+(pix*PAGE_SIZE),
 					      pfn+pix);
 #endif
+		}
 		if (error) {
 			pr_err("%s: vm_insert_pfn returned %d\n",
 			       __func__, error);