diff --git a/configure.in b/configure.in
index 380be6224d27..aa1653261bc2 100644
--- a/configure.in
+++ b/configure.in
@@ -9083,6 +9083,8 @@ if test -z "$MOZ_NATIVE_JEMALLOC" -a "$MOZ_MEMORY" && test -n "$MOZ_JEMALLOC3" -
   if test "$CROSS_COMPILE"; then
     ac_configure_args="$ac_configure_args je_cv_static_page_shift=12"
   fi
+  # Force disable DSS support in jemalloc.
+  ac_configure_args="$ac_configure_args ac_cv_func_sbrk=false"
 
   if ! test -e memory/jemalloc; then
     mkdir -p memory/jemalloc
diff --git a/memory/jemalloc/0005-Bug-1121314-Avoid-needing-the-arena-in-chunk_alloc_d.patch b/memory/jemalloc/0005-Bug-1121314-Avoid-needing-the-arena-in-chunk_alloc_d.patch
new file mode 100644
index 000000000000..89b84dcbbe02
--- /dev/null
+++ b/memory/jemalloc/0005-Bug-1121314-Avoid-needing-the-arena-in-chunk_alloc_d.patch
@@ -0,0 +1,58 @@
+From 722400adde3b4cb307fdc310e6296e10e6ace7ae Mon Sep 17 00:00:00 2001
+From: Mike Hommey <mh+mozilla@glandium.org>
+Date: Wed, 14 Jan 2015 12:49:24 +0900
+Subject: [PATCH] Bug 1121314 - Avoid needing the arena in chunk_alloc_default
+ to avoid possible infinite loops involving a0malloc
+
+---
+ src/chunk.c | 21 +++++++++++++--------
+ 1 file changed, 13 insertions(+), 8 deletions(-)
+
+diff --git a/src/chunk.c b/src/chunk.c
+index 7926452..32e659c 100644
+--- a/src/chunk.c
++++ b/src/chunk.c
+@@ -247,27 +247,32 @@ chunk_alloc_arena(chunk_alloc_t *chunk_alloc, chunk_dalloc_t *chunk_dalloc,
+ 	return (ret);
+ }
+ 
+ /* Default arena chunk allocation routine in the absence of user override. */
+ void *
+ chunk_alloc_default(void *new_addr, size_t size, size_t alignment, bool *zero,
+     unsigned arena_ind)
+ {
+-	arena_t *arena;
++	dss_prec_t dss_prec = dss_prec_disabled;
+ 
+-	arena = arena_get(tsd_fetch(), arena_ind, false, true);
+-	/*
+-	 * The arena we're allocating on behalf of must have been initialized
+-	 * already.
+-	 */
+-	assert(arena != NULL);
++	if (have_dss) {
++		arena_t *arena;
++
++		arena = arena_get(tsd_fetch(), arena_ind, false, true);
++		/*
++		 * The arena we're allocating on behalf of must have been
++		 * initialized already.
++		 */
++		assert(arena != NULL);
++		dss_prec = arena->dss_prec;
++	}
+ 
+ 	return (chunk_alloc_core(new_addr, size, alignment, false, zero,
+-	    arena->dss_prec));
++	    dss_prec));
+ }
+ 
+ static void
+ chunk_record(extent_tree_t *chunks_szad, extent_tree_t *chunks_ad, void *chunk,
+     size_t size)
+ {
+ 	bool unzeroed;
+ 	extent_node_t *xnode, *node, *prev, *xprev, key;
+-- 
+2.2.1.dirty
+
diff --git a/memory/jemalloc/src/src/chunk.c b/memory/jemalloc/src/src/chunk.c
index 7926452729f2..32e659c98c9d 100644
--- a/memory/jemalloc/src/src/chunk.c
+++ b/memory/jemalloc/src/src/chunk.c
@@ -252,17 +252,22 @@ void *
 chunk_alloc_default(void *new_addr, size_t size, size_t alignment, bool *zero,
     unsigned arena_ind)
 {
-	arena_t *arena;
+	dss_prec_t dss_prec = dss_prec_disabled;
 
-	arena = arena_get(tsd_fetch(), arena_ind, false, true);
-	/*
-	 * The arena we're allocating on behalf of must have been initialized
-	 * already.
-	 */
-	assert(arena != NULL);
+	if (have_dss) {
+		arena_t *arena;
+
+		arena = arena_get(tsd_fetch(), arena_ind, false, true);
+		/*
+		 * The arena we're allocating on behalf of must have been
+		 * initialized already.
+		 */
+		assert(arena != NULL);
+		dss_prec = arena->dss_prec;
+	}
 
 	return (chunk_alloc_core(new_addr, size, alignment, false, zero,
-	    arena->dss_prec));
+	    dss_prec));
 }
 
 static void
diff --git a/memory/jemalloc/update.sh b/memory/jemalloc/update.sh
index a2b34821b3f5..0f763154562a 100755
--- a/memory/jemalloc/update.sh
+++ b/memory/jemalloc/update.sh
@@ -18,6 +18,7 @@ patch -p1 < ../0001-Dont-overwrite-VERSION-on-a-git-repository.patch
 patch -p1 < ../0002-Move-variable-declaration-to-the-top-its-block-for-M.patch
 patch -p1 < ../0003-Add-a-isblank-definition-for-MSVC-2013.patch
 patch -p1 < ../0004-Implement-stats.bookkeeping.patch
+patch -p1 < ../0005-Bug-1121314-Avoid-needing-the-arena-in-chunk_alloc_d.patch
 
 cd ..
 hg addremove -q src