--- zzzz-none-000/linux-3.10.107/arch/mips/include/asm/checksum.h	2017-06-27 09:49:32.000000000 +0000
+++ vr9-7490-729/linux-3.10.107/arch/mips/include/asm/checksum.h	2021-11-10 11:53:53.000000000 +0000
@@ -31,6 +31,12 @@
 
 __wsum __csum_partial_copy_user(const void *src, void *dst,
 				int len, __wsum sum, int *err_ptr);
+#ifdef  CONFIG_EVA
+__wsum __csum_partial_copy_fromuser(const void *src, void *dst,
+				    int len, __wsum sum, int *err_ptr);
+__wsum __csum_partial_copy_touser(const void *src, void *dst,
+				  int len, __wsum sum, int *err_ptr);
+#endif
 
 /*
  * this is a new version of the above that records errors it finds in *errp,
@@ -40,9 +46,34 @@
 __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len,
 				   __wsum sum, int *err_ptr)
 {
+#ifndef CONFIG_EVA
 	might_fault();
 	return __csum_partial_copy_user((__force void *)src, dst,
-					len, sum, err_ptr);
+					    len, sum, err_ptr);
+#else
+	if (segment_eq(get_fs(), KERNEL_DS))
+		return __csum_partial_copy_user((__force void *)src, dst,
+						len, sum, err_ptr);
+	else {
+		might_fault();
+		return __csum_partial_copy_fromuser((__force void *)src, dst,
+						    len, sum, err_ptr);
+	}
+#endif
+}
+
+#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
+static inline
+__wsum csum_and_copy_from_user (const void __user *src, void *dst,
+				      int len, __wsum sum, int *err_ptr)
+{
+	if (access_ok(VERIFY_READ, src, len))
+		return csum_partial_copy_from_user(src, dst, len, sum, err_ptr);
+
+	if (len)
+		*err_ptr = -EFAULT;
+
+	return sum;
 }
 
 /*
@@ -53,10 +84,22 @@
 __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
 			     __wsum sum, int *err_ptr)
 {
-	might_fault();
-	if (access_ok(VERIFY_WRITE, dst, len))
+	if (access_ok(VERIFY_WRITE, dst, len)) {
+#ifndef CONFIG_EVA
+		might_fault();
 		return __csum_partial_copy_user(src, (__force void *)dst,
-						len, sum, err_ptr);
+						  len, sum, err_ptr);
+#else
+		if (segment_eq(get_fs(), KERNEL_DS))
+			return __csum_partial_copy_user(src, (__force void *)dst,
+							  len, sum, err_ptr);
+		else {
+			might_fault();
+			return __csum_partial_copy_touser(src, (__force void *)dst,
+							  len, sum, err_ptr);
+		}
+#endif
+	}
 	if (len)
 		*err_ptr = -EFAULT;