diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index a5df627b..ad135b64 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c
@@ -1934,7 +1934,7 @@ SYSCALL_DECLARE(mmap)
 		;
 
 	const uintptr_t addr0 = ihk_mc_syscall_arg0(ctx);
-	const size_t len0 = ihk_mc_syscall_arg1(ctx);
+	size_t len0 = ihk_mc_syscall_arg1(ctx);
 	const int prot = ihk_mc_syscall_arg2(ctx);
 	const int flags0 = ihk_mc_syscall_arg3(ctx);
 	const int fd = ihk_mc_syscall_arg4(ctx);
@@ -1993,6 +1993,8 @@ SYSCALL_DECLARE(mmap)
 			goto out;
 		}
 		pgsize = (size_t)1 << ((flags >> MAP_HUGE_SHIFT) & 0x3F);
+		/* Round-up map length by pagesize */
+		len0 = ALIGN(len0, pgsize);
 
 		if (rusage_check_overmap(len0,
 				(flags >> MAP_HUGE_SHIFT) & 0x3F)) {
diff --git a/arch/x86_64/kernel/syscall.c b/arch/x86_64/kernel/syscall.c
index a3d8c935..602dcf1c 100644
--- a/arch/x86_64/kernel/syscall.c
+++ b/arch/x86_64/kernel/syscall.c
@@ -1668,7 +1668,7 @@ SYSCALL_DECLARE(mmap)
 		;
 
 	const uintptr_t addr0 = ihk_mc_syscall_arg0(ctx);
-	const size_t len0 = ihk_mc_syscall_arg1(ctx);
+	size_t len0 = ihk_mc_syscall_arg1(ctx);
 	const int prot = ihk_mc_syscall_arg2(ctx);
 	const int flags0 = ihk_mc_syscall_arg3(ctx);
 	const int fd = ihk_mc_syscall_arg4(ctx);
@@ -1725,6 +1725,8 @@ SYSCALL_DECLARE(mmap)
 		}
 
 		pgsize = (size_t)1 << ((flags >> MAP_HUGE_SHIFT) & 0x3F);
+		/* Round-up map length by pagesize */
+		len0 = ALIGN(len0, pgsize);
 
 		if (rusage_check_overmap(len0,
 				(flags >> MAP_HUGE_SHIFT) & 0x3F)) {