diff -r 2fd64ea0a7cb -r db1914925f02 src/arch/arm/pmu.cc
--- a/src/arch/arm/pmu.cc	Tue Mar 08 17:51:02 2016 -0500
+++ b/src/arch/arm/pmu.cc	Thu Mar 10 14:42:23 2016 +0000
@@ -574,8 +574,6 @@
     const uint64_t msb(1ULL << (overflow64 ? 63 : 31));
     const uint64_t old_value(value);
 
-    assert(delta > 0);
-
     value += delta;
 
     // Overflow if the msb goes from 1 to 0