The deadlock happens in the debug jvm while verifying the code cache
as part of the gc_epilogue:

#0 0x40065f09 in sigsuspend () from /lib/i686/libc.so.6
#1 0x4002c6b8 in __pthread_wait_for_restart_signal () from /lib/i686/libpthread.so.0
#2 0x4002dfc0 in __pthread_alt_lock () from /lib/i686/libpthread.so.0
#3 0x4002aea7 in pthread_mutex_lock () from /lib/i686/libpthread.so.0
#4 0x407dfdff in os::Linux::safe_mutex_lock(pthread_mutex_t*) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#5 0x407aa8f4 in Mutex::lock(Thread*) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#6 0x407aaabf in Mutex::lock() () from /usr/j2se/jre/lib/i386/server/libjvm.so
#7 0x407b75a4 in nmethod::verify_interrupt_point(unsigned char*) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#8 0x407b7826 in nmethod::verify_scopes() () from /usr/j2se/jre/lib/i386/server/libjvm.so
#9 0x407b7381 in nmethod::verify() () from /usr/j2se/jre/lib/i386/server/libjvm.so
#10 0x403bd157 in CodeCache::gc_epilogue() () from /usr/j2se/jre/lib/i386/server/libjvm.so
#11 0x403ff91b in CMSCollector::checkpointRootsFinalWork(int, int, int, int) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#12 0x403ff004 in CMSCollector::checkpointRootsFinal(int, int, int) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#13 0x40404ce4 in CMSCollector::do_CMS_operation(CMSCollector::CMS_op_type) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#14 0x40404e8b in CMSCollector::stop_world_and_do(CMSCollector::CMS_op_type) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#15 0x403f7674 in CMSCollector::collect_in_background(int) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#16 0x4040f1b2 in ConcurrentMarkSweepThread::run() () from /usr/j2se/jre/lib/i386/server/libjvm.so
#17 0x407e11c9 in _start(Thread*) () from /usr/j2se/jre/lib/i386/server/libjvm.so
#18 0x4002a020 in pthread_start_thread () from /lib/i686/libpthread.so.0