--- a/hotspot/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp Tue Nov 08 16:30:36 2016 +0100
+++ b/hotspot/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp Mon Dec 19 15:48:57 2016 -0800
@@ -839,19 +839,20 @@
////////////////////////////////////////////////////////////////////////////////
// thread stack
-#ifdef AMD64
-size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
-size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
+// Minimum usable stack sizes required to get to user code. Space for
+// HotSpot guard pages is added later.
+size_t os::Posix::_compiler_thread_min_stack_allowed = 48 * K;
+size_t os::Posix::_java_thread_min_stack_allowed = 48 * K;
+#ifdef _LP64
size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
#else
-size_t os::Posix::_compiler_thread_min_stack_allowed = (48 DEBUG_ONLY(+ 4)) * K;
-size_t os::Posix::_java_thread_min_stack_allowed = (48 DEBUG_ONLY(+ 4)) * K;
size_t os::Posix::_vm_internal_thread_min_stack_allowed = (48 DEBUG_ONLY(+ 4)) * K;
+#endif // _LP64
+#ifndef AMD64
#ifdef __GNUC__
#define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;})
#endif
-
#endif // AMD64
// return default stack size for thr_type