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Reading symbols from xl...done.
(gdb) run
Starting program: /usr/sbin/xl create gent2014.harden.hvm
warning: Cannot call inferior functions, Linux kernel PaX protection forbids return to non-executable pages!
warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Parsing config from gent2014.harden.hvm
xc: info: VIRTUAL MEMORY ARRANGEMENT:
  Loader:        0000000000100000->00000000001a0a28
  Modules:       0000000000000000->0000000000000000
  TOTAL:         0000000000000000->000000003f000000
  ENTRY ADDRESS: 0000000000100000
xc: info: PHYSICAL MEMORY ALLOCATION:
  4KB PAGES: 0x0000000000000200
  2MB PAGES: 0x00000000000001f7
  1GB PAGES: 0x0000000000000000
[New Thread 0x7c6687bdb700 (LWP 14357)]
Daemon running with PID 14471

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7c6687bdb700 (LWP 14357)]
0x00007c6685492854 in execute_stack_op (op_ptr=0x7c6686f147cb "w\240\001\006\020\b\002w(\020\t\002w0\020\n\002w8\020\v\003w\300", 
    op_end=0x7c6686f147cf "\020\b\002w(\020\t\002w0\020\n\002w8\020\v\003w\300", context=context@entry=0x7c6687bda190, initial=initial@entry=0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c:516
516     /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c: No such file or directory.
(gdb) backtrace 
#0  0x00007c6685492854 in execute_stack_op (op_ptr=0x7c6686f147cb "w\240\001\006\020\b\002w(\020\t\002w0\020\n\002w8\020\v\003w\300", 
    op_end=0x7c6686f147cf "\020\b\002w(\020\t\002w0\020\n\002w8\020\v\003w\300", context=context@entry=0x7c6687bda190, initial=initial@entry=0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c:516
#1  0x00007c66854932b4 in uw_update_context_1 (context=context@entry=0x7c6687bda5a0, fs=fs@entry=0x7c6687bda2f0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c:1424
#2  0x00007c6685493635 in uw_update_context (context=context@entry=0x7c6687bda5a0, fs=fs@entry=0x7c6687bda2f0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c:1506
#3  0x00007c66854943e6 in uw_advance_context (fs=0x7c6687bda2f0, context=0x7c6687bda5a0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind-dw2.c:1529
#4  _Unwind_ForcedUnwind_Phase2 (exc=exc@entry=0x7c6687bdbd70, context=context@entry=0x7c6687bda5a0)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind.inc:185
#5  0x00007c6685494770 in _Unwind_ForcedUnwind (exc=0x7c6687bdbd70, stop=stop@entry=0x7c6686f0cbd0 <unwind_stop>, stop_argument=<optimized out>)
    at /var/tmp/portage/sys-devel/gcc-4.8.3/work/gcc-4.8.3/libgcc/unwind.inc:207
#6  0x00007c6686f0cd60 in __GI___pthread_unwind (buf=<optimized out>) at unwind.c:129
#7  0x00007c6686f04aab in __do_cancel () at ../nptl/pthreadP.h:280
#8  sigcancel_handler (sig=<optimized out>, si=<optimized out>, ctx=<optimized out>) at nptl-init.c:214
#9  sigcancel_handler (sig=<optimized out>, si=<optimized out>, ctx=<optimized out>) at nptl-init.c:173
#10 <signal handler called>
#11 0x00007c6686f0d43d in read () at ../sysdeps/unix/syscall-template.S:81
#12 0x00007c66867244e7 in read (__nbytes=16, __buf=0x7c66800008d0, __fd=6) at /usr/include/bits/unistd.h:44
#13 read_all (fd=6, data=0x7c66800008d0, data@entry=0x20, len=len@entry=16, nonblocking=nonblocking@entry=0) at xs.c:374
#14 0x00007c6686724616 in read_message (h=h@entry=0xebe345f9c50, nonblocking=nonblocking@entry=0) at xs.c:1139
#15 0x00007c6686724ffe in read_thread (arg=0xebe345f9c50) at xs.c:1211
#16 0x00007c6686f0623a in start_thread (arg=0x7c6687bdb700) at pthread_create.c:309
#17 0x00007c6686c4522d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
(gdb) quit