diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c
index 7713e7a6f476..432cf0b97a13 100644
--- a/arch/um/kernel/ksyms.c
+++ b/arch/um/kernel/ksyms.c
@@ -39,7 +39,6 @@ EXPORT_SYMBOL(um_virt_to_phys);
 EXPORT_SYMBOL(mode_tt);
 EXPORT_SYMBOL(handle_page_fault);
 EXPORT_SYMBOL(find_iomem);
-EXPORT_SYMBOL(end_iomem);
 
 #ifdef CONFIG_MODE_TT
 EXPORT_SYMBOL(strncpy_from_user_tt);
@@ -89,12 +88,10 @@ EXPORT_SYMBOL(dump_thread);
 EXPORT_SYMBOL(do_gettimeofday);
 EXPORT_SYMBOL(do_settimeofday);
 
-/* This is here because UML expands open to sys_open, not to a system
+/* This is here because UML expands lseek to sys_lseek, not to a system
  * call instruction.
  */
-EXPORT_SYMBOL(sys_open);
 EXPORT_SYMBOL(sys_lseek);
-EXPORT_SYMBOL(sys_read);
 EXPORT_SYMBOL(sys_wait4);
 
 #ifdef CONFIG_SMP
diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c
index 8da6ab31152a..2598158e1f53 100644
--- a/arch/um/os-Linux/user_syms.c
+++ b/arch/um/os-Linux/user_syms.c
@@ -18,14 +18,19 @@ extern void *memmove(void *, const void *, size_t);
 extern void *memset(void *, int, size_t);
 extern int printf(const char *, ...);
 
+/* If they're not defined, the export is included in lib/string.c.*/
+#ifdef __HAVE_ARCH_STRLEN
 EXPORT_SYMBOL(strlen);
+#endif
+#ifdef __HAVE_ARCH_STRSTR
+EXPORT_SYMBOL(strstr);
+#endif
+
 EXPORT_SYMBOL(memcpy);
 EXPORT_SYMBOL(memmove);
 EXPORT_SYMBOL(memset);
 EXPORT_SYMBOL(printf);
 
-EXPORT_SYMBOL(strstr);
-
 /* Here, instead, I can provide a fake prototype. Yes, someone cares: genksyms.
  * However, the modules will use the CRC defined *here*, no matter if it is
  * good; so the versions of these symbols will always match
diff --git a/arch/um/sys-i386/ksyms.c b/arch/um/sys-i386/ksyms.c
index db524ab3f743..2a1eac1859ce 100644
--- a/arch/um/sys-i386/ksyms.c
+++ b/arch/um/sys-i386/ksyms.c
@@ -15,7 +15,3 @@ EXPORT_SYMBOL(__up_wakeup);
 
 /* Networking helper routines. */
 EXPORT_SYMBOL(csum_partial);
-
-/* delay core functions */
-EXPORT_SYMBOL(__const_udelay);
-EXPORT_SYMBOL(__udelay);