diff --git a/arch/alpha/lib/csum_partial_copy.c b/arch/alpha/lib/csum_partial_copy.c
index ff3c10721caf..5675dca8dbb1 100644
--- a/arch/alpha/lib/csum_partial_copy.c
+++ b/arch/alpha/lib/csum_partial_copy.c
@@ -378,6 +378,11 @@ csum_partial_copy_from_user(const void __user *src, void *dst, int len,
 __wsum
 csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
 {
-	return csum_partial_copy_from_user((__force const void __user *)src,
-			dst, len, sum, NULL);
+	__wsum checksum;
+	mm_segment_t oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	checksum = csum_partial_copy_from_user((__force const void __user *)src,
+						dst, len, sum, NULL);
+	set_fs(oldfs);
+	return checksum;
 }