diff -Nru glibc-2.21/debian/changelog glibc-2.21/debian/changelog
--- glibc-2.21/debian/changelog	2015-03-23 15:37:59.000000000 +0000
+++ glibc-2.21/debian/changelog	2015-03-25 21:43:17.000000000 +0000
@@ -1,3 +1,12 @@
+glibc (2.21-0ubuntu4) vivid; urgency=medium
+
+  * debian/patches/arm/local-arm-futex.diff: Lie about the minimum
+    kernel support for futex_atomic_cmpxchg_inatomic to restore the
+    previous state and make pulsesink happier on ARM (LP: #1436162)
+  * debian/debhelper.in/libc.preinst: Wipe ld.so.cache on upgrades.
+
+ -- Adam Conrad <adconrad@ubuntu.com>  Wed, 25 Mar 2015 14:31:51 -0600
+
 glibc (2.21-0ubuntu3) vivid; urgency=medium
 
   * debian/patches/ubuntu/local-warn-bsd-source.diff: Don't warn on
diff -Nru glibc-2.21/debian/debhelper.in/libc.preinst glibc-2.21/debian/debhelper.in/libc.preinst
--- glibc-2.21/debian/debhelper.in/libc.preinst	2015-03-16 16:13:23.000000000 +0000
+++ glibc-2.21/debian/debhelper.in/libc.preinst	2015-03-25 21:33:01.000000000 +0000
@@ -529,7 +529,7 @@
 esac
 
 if [ -n "$preversion" ]; then
-    if dpkg --compare-versions "$preversion" lt 2.16; then
+    if dpkg --compare-versions "$preversion" lt 2.21-0ubuntu4; then
        # upgrading from a pre-multiarch libc to a multiarch libc; we have
        # to blow away /etc/ld.so.cache, otherwise the old unpacked libc
        # is still first in the cache and segfaults when combined with
diff -Nru glibc-2.21/debian/patches/arm/local-arm-futex.diff glibc-2.21/debian/patches/arm/local-arm-futex.diff
--- glibc-2.21/debian/patches/arm/local-arm-futex.diff	1970-01-01 00:00:00.000000000 +0000
+++ glibc-2.21/debian/patches/arm/local-arm-futex.diff	2015-03-25 20:31:27.000000000 +0000
@@ -0,0 +1,22 @@
+Description: Lie about futex_atomic_cmpxchg_inatomic kernel support.
+ In past versions of glibc, we incorrectly assumed all ARM kernels
+ in all configurations supported futex_atomic_cmpxchg_inatomic. This
+ was clearly a lie, however it was a lie that we relied on, because
+ the fallback implementation appears to not play nicely with certain
+ applications like pulseaudio.  Restore the lie for kernels > 2.6.32
+ and plug our ears and scream "LA LA LA" about how wrong this is.
+Author: Adam Conrad <adconrad@ubuntu.com>
+Bug-Ubuntu: https://launchpad.net/bugs/1436162
+Last-Update: 2015-03-25
+
+--- glibc-2.21.orig/sysdeps/unix/sysv/linux/arm/kernel-features.h
++++ glibc-2.21/sysdeps/unix/sysv/linux/arm/kernel-features.h
+@@ -37,7 +37,7 @@
+ /* The ARM kernel before 3.14.3 may or may not support
+    futex_atomic_cmpxchg_inatomic, depending on kernel
+    configuration.  */
+-#if __LINUX_KERNEL_VERSION < 0x030E03
++#if __LINUX_KERNEL_VERSION < 0x020620
+ # undef __ASSUME_FUTEX_LOCK_PI
+ # undef __ASSUME_REQUEUE_PI
+ # undef __ASSUME_SET_ROBUST_LIST
diff -Nru glibc-2.21/debian/patches/series glibc-2.21/debian/patches/series
--- glibc-2.21/debian/patches/series	2015-03-23 15:03:22.000000000 +0000
+++ glibc-2.21/debian/patches/series	2015-03-25 21:08:16.000000000 +0000
@@ -54,6 +54,7 @@
 arm/unsubmitted-ldso-multilib.diff
 arm/cvs-arm-sfi_breg.diff
 arm/cvs-memcpy-memmove-always-bx.diff
+arm/local-arm-futex.diff
 
 hppa/local-inlining.diff
 hppa/local-stack-grows-up.diff