diff --git a/arch/x86/include/asm/posix_types.h b/arch/x86/include/asm/posix_types.h
index 5529f32702..717f6cb8e0 100644
--- a/arch/x86/include/asm/posix_types.h
+++ b/arch/x86/include/asm/posix_types.h
@@ -16,8 +16,13 @@ typedef int		__kernel_pid_t;
 typedef unsigned short	__kernel_ipc_pid_t;
 typedef unsigned short	__kernel_uid_t;
 typedef unsigned short	__kernel_gid_t;
+#if CONFIG_IS_ENABLED(X86_64)
+typedef unsigned long	__kernel_size_t;
+typedef long		__kernel_ssize_t;
+#else
 typedef unsigned int	__kernel_size_t;
 typedef int		__kernel_ssize_t;
+#endif
 typedef int		__kernel_ptrdiff_t;
 typedef long		__kernel_time_t;
 typedef long		__kernel_suseconds_t;
diff --git a/arch/x86/include/asm/types.h b/arch/x86/include/asm/types.h
index 880dcb488a..a47e581fe3 100644
--- a/arch/x86/include/asm/types.h
+++ b/arch/x86/include/asm/types.h
@@ -44,7 +44,12 @@ typedef __INT64_TYPE__ s64;
 typedef __UINT64_TYPE__ u64;
 #endif
 
+#if CONFIG_IS_ENABLED(X86_64)
+#define BITS_PER_LONG 64
+#else
 #define BITS_PER_LONG 32
+#endif
+
 /* Dma addresses are 32-bits wide.  */
 
 typedef u32 dma_addr_t;