diff --git a/ChangeLog b/ChangeLog
index 9db957d06e..574abe16a4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2014-03-19  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #16649]
+	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
+	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PREADV): Undefine.
+	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PWRITEV): Likewise.
+	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
+	(__ASSUME_PREADV): Undefine.
+	(__ASSUME_PWRITEV): Likewise.
+
 2014-03-18  Roland McGrath  <roland@hack.frob.com>
 
 	* bits/mman-linux.h: Add comment about non-Linux use.
diff --git a/NEWS b/NEWS
index df5507afcb..5f9ffcc569 100644
--- a/NEWS
+++ b/NEWS
@@ -10,8 +10,8 @@ Version 2.20
 * The following bugs are resolved with this release:
 
   15347, 15804, 15894, 16447, 16532, 16545, 16574, 16600, 16609, 16610,
-  16611, 16613, 16623, 16632, 16639, 16642, 16670, 16674, 16677, 16680,
-  16683, 16689, 16695, 16701, 16706, 16707.
+  16611, 16613, 16623, 16632, 16639, 16642, 16649, 16670, 16674, 16677,
+  16680, 16683, 16689, 16695, 16701, 16706, 16707.
 
 * Running the testsuite no longer terminates as soon as a test fails.
   Instead, a file tests.sum (xtests.sum from "make xcheck") is generated,
diff --git a/sysdeps/unix/sysv/linux/alpha/kernel-features.h b/sysdeps/unix/sysv/linux/alpha/kernel-features.h
index e691bb0e1e..f3a7a555c0 100644
--- a/sysdeps/unix/sysv/linux/alpha/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/alpha/kernel-features.h
@@ -93,4 +93,10 @@
 # define __ASSUME_FDATASYNC	1
 #endif
 
+/* Support for preadv and pwritev was added for alpha in 2.6.33.  */
+#if __LINUX_KERNEL_VERSION < 0x020621
+# undef __ASSUME_PREADV
+# undef __ASSUME_PWRITEV
+#endif
+
 #endif /* _KERNEL_FEATURES_H */
diff --git a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
index dfb83443c1..f9a61a9415 100644
--- a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
@@ -43,5 +43,8 @@
 
 #include_next <kernel-features.h>
 
-/* The MicroBlaze kernel does not support the pselect6 syscall.  */
+/* The MicroBlaze kernel does not support the pselect6, preadv and
+   pwritev syscalls.  */
 #undef __ASSUME_PSELECT
+#undef __ASSUME_PREADV
+#undef __ASSUME_PWRITEV