Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Grundmann, Christian (Christian.Grundmann@fabasoft.com) wrote:
> And here another one

Oh this is a bit of a different one, from query-blockstats, although again if
the heap's corrupted it might have just been the first guy to trip over the
corrupt part afterwards.

Dave

> Thread 1 (Thread 0x7f5d03ba5c00 (LWP 1507)):
> #0  0x00007f5cff7e2e7d in tcmalloc::CentralFreeList::FetchFromOneSpans(int, void**, void**) () from /lib64/libtcmalloc.so.4
> No symbol table info available.
> #1  0x00007f5cff7e312a in tcmalloc::CentralFreeList::FetchFromOneSpansSafe(int, void**, void**) () from /lib64/libtcmalloc.so.4
> No symbol table info available.
> #2  0x00007f5cff7e31dd in tcmalloc::CentralFreeList::RemoveRange(void**, void**, int) () from /lib64/libtcmalloc.so.4
> No symbol table info available.
> #3  0x00007f5cff7e6235 in tcmalloc::ThreadCache::FetchFromCentralCache(unsigned long, unsigned long) () from /lib64/libtcmalloc.so.4
> No symbol table info available.
> #4  0x00007f5cff7f4d5b in tc_malloc () from /lib64/libtcmalloc.so.4
> No symbol table info available.
> #5  0x00007f5d03d61489 in malloc_and_trace (n_bytes=18) at vl.c:2575
>         ptr = 0x1
> #6  0x00007f5d020b647f in g_malloc () from /lib64/libglib-2.0.so.0
> No symbol table info available.
> #7  0x00007f5d020cdf7f in g_strdup () from /lib64/libglib-2.0.so.0
> No symbol table info available.
> #8  0x00007f5d03eddab5 in alloc_entry (value=0x7f5d088de6c0, key=0x7f5d03f5debb "wr_highest_offset") at qobject/qdict.c:79
>         entry = 0x7f5d088df480
> #9  qdict_put_obj (qdict=0x7f5d06e10400, key=0x7f5d03f5debb "wr_highest_offset", value=0x7f5d088de6c0) at qobject/qdict.c:145
>         bucket = 81
>         entry = <optimized out>
> #10 0x00007f5d03ebf34a in visit_type_BlockDeviceStats_fields (errp=0x7ffddb417ca0, obj=0x7f5d07f905a0, m=0x7f5d061fdea0) at qapi-visit.c:1542
>         err = 0x0
> #11 visit_type_BlockDeviceStats (m=m@entry=0x7f5d061fdea0, obj=0x7f5d07f905a0, name=name@entry=0x7f5d03f032ec "stats", errp=errp@entry=0x7ffddb417ca0) at qapi-visit.c:1566
>         err = 0x0
> #12 0x00007f5d03ebf5b1 in visit_type_BlockStats_fields (errp=0x7ffddb417cf0, obj=0x7f5d07f90650, m=0x7f5d061fdea0) at qapi-visit.c:1614
>         err = 0x0
> #13 visit_type_BlockStats (m=m@entry=0x7f5d061fdea0, obj=0x7f5d07f90650, name=name@entry=0x7f5d03f480f4 "parent", errp=errp@entry=0x7ffddb417cf0) at qapi-visit.c:1644
>         err = 0x0
> #14 0x00007f5d03ebf6bd in visit_type_BlockStats_fields (errp=0x7ffddb417d38, obj=0x7f5d07c67a50, m=0x7f5d061fdea0) at qapi-visit.c:1620
>         err = 0x0
> #15 visit_type_BlockStats (m=m@entry=0x7f5d061fdea0, obj=0x7f5d07c67a50, name=name@entry=0x0, errp=errp@entry=0x7ffddb417d38) at qapi-visit.c:1644
>         err = 0x0
> #16 0x00007f5d03ebf760 in visit_type_BlockStatsList (m=0x7f5d061fdea0, obj=obj@entry=0x7ffddb417d98, name=name@entry=0x7f5d03f00e6e "unused", errp=errp@entry=0x7ffddb417da0) at qapi-visit.c:1665
>         native_i = <optimized out>
>         err = 0x0
>         i = 0x7f5d07c67a50
>         prev = 0x7ffddb417d40
> #17 0x00007f5d03d674dd in qmp_marshal_output_query_blockstats (errp=0x7ffddb417d90, ret_out=0x7ffddb417e10, ret_in=0x7f5d07c67120) at qmp-marshal.c:182
>         local_err = 0x0
>         mo = 0x7f5d061fdea0
>         md = <optimized out>
>         v = <optimized out>
> #18 qmp_marshal_input_query_blockstats (mon=<optimized out>, qdict=<optimized out>, ret=0x7ffddb417e10) at qmp-marshal.c:225
>         local_err = 0x0
>         args = <optimized out>
>         retval = <optimized out>
>         mi = 0x7f5d064e2000
>         md = <optimized out>
>         v = <optimized out>
>         has_query_nodes = false
>         query_nodes = false
> #19 0x00007f5d03ca0531 in qmp_call_cmd (cmd=<optimized out>, params=0x7f5d075dd600, mon=0x7f5d06208320) at /usr/src/debug/qemu-2.3.0/monitor.c:5051
>         ret = <optimized out>
>         data = 0x0
> #20 handle_qmp_command (parser=<optimized out>, tokens=<optimized out>) at /usr/src/debug/qemu-2.3.0/monitor.c:5113
>         err = <optimized out>
>         obj = <optimized out>
>         input = <optimized out>
>         args = 0x7f5d075dd600
>         cmd_name = <optimized out>
>         mon = 0x7f5d06208320
> #21 0x00007f5d03edf4f2 in json_message_process_token (lexer=0x7f5d061f5d70, token=0x7f5d061991e0, type=JSON_OPERATOR, x=48, y=15) at qobject/json-streamer.c:87
>         parser = 0x7f5d061f5d68
>         dict = 0x7f5d088ea800
> #22 0x00007f5d03ef191f in json_lexer_feed_char (lexer=lexer@entry=0x7f5d061f5d70, ch=<optimized out>, flush=flush@entry=false) at qobject/json-lexer.c:303
>         new_state = 100
> #23 0x00007f5d03ef19ee in json_lexer_feed (lexer=0x7f5d061f5d70, buffer=<optimized out>, size=<optimized out>) at qobject/json-lexer.c:356
>         err = <optimized out>
>         i = <optimized out>
> #24 0x00007f5d03edf689 in json_message_parser_feed (parser=<optimized out>, buffer=<optimized out>, size=<optimized out>) at qobject/json-streamer.c:110
> No locals.
> #25 0x00007f5d03c9e8cf in monitor_control_read (opaque=<optimized out>, buf=<optimized out>, size=<optimized out>) at /usr/src/debug/qemu-2.3.0/monitor.c:5134
>         old_mon = 0x0
> #26 0x00007f5d03d5b1b0 in qemu_chr_be_write (len=<optimized out>, buf=0x7ffddb417f40 "}\177A\333\375\177", s=0x7f5d0625a2e0) at qemu-char.c:305
> No locals.
> #27 tcp_chr_read (chan=<optimized out>, cond=<optimized out>, opaque=0x7f5d0625a2e0) at qemu-char.c:2870
>         chr = 0x7f5d0625a2e0
>         s = 0x7f5d061aa3f0
>         buf = "}\177A\333\375\177\000\000\360\360\355\003]\177\000\000\030\003\000\000\000\000\000\000\205\336\355\003]\177\000\000\000A\036\b]\177\000\000\263\325\355\003]\177\000\000\000A\036\b]\177", '\000' <repeats 18 times>, "`2\036\b]\177\000\000ЀA\333\375\177\000\000\000\000\000\000\000\000\000\000 \232\261\a]\177\000\000\000(\341\006]\177\000\000P\217A\333\375\177\000\000H\242<\374\\\177\000\000]\000\000\000\000\000\000\000\060\000\000\000\060\000\000\000\240\200A\333\375\177\000\000\340\177A\333\375\177\000\000\r\000\000\000\000\000\000\000 Xz\b]\177\000\000\000@&\006]\177\000\000\340\365\215\b]\177\000\000Q\000\000\000\000\000\000\000\232"...
>         len = <optimized out>
>         size = <optimized out>
> #28 0x00007f5d020b099a in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
> No symbol table info available.
> #29 0x00007f5d03e74288 in glib_pollfds_poll () at main-loop.c:209
>         context = 0x7f5d06205140
>         pfds = <optimized out>
> #30 os_host_main_loop_wait (timeout=<optimized out>) at main-loop.c:254
>         ret = 2
>         spin_counter = 0
> #31 main_loop_wait (nonblocking=<optimized out>) at main-loop.c:503
>         ret = 2
>         timeout = 4294967295
>         timeout_ns = <optimized out>
> #32 0x00007f5d03c73a4e in main_loop () at vl.c:1818
>         nonblocking = <optimized out>
>         last_io = 2
> #33 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4394
>         i = <optimized out>
>         snapshot = <optimized out>
>         linux_boot = <optimized out>
>         initrd_filename = <optimized out>
>         kernel_filename = <optimized out>
>         kernel_cmdline = <optimized out>
>         boot_order = 0x7f5d03f06a67 "cad"
>         boot_once = 0x0
>         cyls = <optimized out>
>         heads = <optimized out>
>         secs = <optimized out>
>         translation = <optimized out>
>         hda_opts = <optimized out>
>         opts = <optimized out>
>         machine_opts = <optimized out>
>         icount_opts = <optimized out>
>         olist = <optimized out>
>         optind = 67
>         optarg = 0x7f5d06193570 "rhel6.5.0"
>         loadvm = <optimized out>
>         machine_class = <optimized out>
>         cpu_model = <optimized out>
>         vga_model = 0x0
>         qtest_chrdev = <optimized out>
>         qtest_log = <optimized out>
>         pid_file = <optimized out>
>         incoming = <optimized out>
>         show_vnc_port = <optimized out>
>         defconfig = <optimized out>
>         userconfig = 56
>         log_mask = <optimized out>
>         log_file = <optimized out>
>         mem_trace = {malloc = 0x7f5d03d61480 <malloc_and_trace>, realloc = 0x7f5d03d61460 <realloc_and_trace>, free = 0x7f5d03d61450 <free_and_trace>, calloc = 0x0, try_malloc = 0x0, try_realloc = 0x0}
>         trace_events = <optimized out>
>         trace_file = <optimized out>
>         maxram_size = <optimized out>
>         ram_slots = <optimized out>
>         vmstate_dump_file = <optimized out>
>         main_loop_err = 0x0
>         __func__ = "main"
> 
> 
> 
> 
> -----Ursprüngliche Nachricht-----
> Von: qemu-devel-bounces+christian.grundmann=fabasoft.com@nongnu.org [mailto:qemu-devel-bounces+christian.grundmann=fabasoft.com@nongnu.org] Im Auftrag von Grundmann, Christian
> Gesendet: Dienstag, 17. November 2015 15:12
> An: 'Dr. David Alan Gilbert' <dgilbert@redhat.com>
> Cc: 'qemu-devel@nongnu.org' <qemu-devel@nongnu.org>; stefanha@redhat.com
> Betreff: Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc
> 
> Here you go
> 
> 
> gdb --batch /usr/libexec/qemu-kvm core.52281.1447709011.dump -ex "set pagination off" -ex "thread apply all bt full"
> [New LWP 52281]
> [New LWP 52288]
> [New LWP 52286]
> [New LWP 52291]
> [New LWP 52292]
> [New LWP 52287]
> [New LWP 52293]
> [New LWP 52290]
> [New LWP 56455]
> [New LWP 52289]
> [New LWP 52282]
> [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1".
> Core was generated by `/usr/libexec/qemu-kvm -name myvmname -S -machine rhel6.5.0,accel=kvm,us'.
> Program terminated with signal 11, Segmentation fault.
> #0  0x00007f6d52d37be1 in tc_malloc () from /lib64/libtcmalloc.so.4
> 
> Thread 11 (Thread 0x7f6d47719700 (LWP 52282)):
> #0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
> No locals.
> #1  0x00007f6d57426272 in futex_wait (val=4294967295, ev=0x7f6d57cf0f44 <rcu_call_ready_event>) at util/qemu-thread-posix.c:301 No locals.
> #2  qemu_event_wait (ev=ev@entry=0x7f6d57cf0f44 <rcu_call_ready_event>) at util/qemu-thread-posix.c:399
>         value = <optimized out>
> #3  0x00007f6d57434526 in call_rcu_thread (opaque=<optimized out>) at util/rcu.c:233
>         tries = 0
>         n = <optimized out>
>         node = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d47719700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d47719700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107326789376, 5884348200482620104, 0, 140107326790080, 140107326789376, 140107592666688, -5804038895876586808, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 10 (Thread 0x7f6d44f14700 (LWP 52289)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c8a4000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d44f139e0, reg_save_area = 0x7f6d44f139a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c8a4000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570cf000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c8a4000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c8a4000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d44f14700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d44f14700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107284825856, 5884348200482620104, 0, 140107284826560, 140107284825856, 140726431086992, -5804033392412867896, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 9 (Thread 0x7f6ab1dff700 (LWP 56455)):
> #0  sem_timedwait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/sem_timedwait.S:101
> No locals.
> #1  0x00007f6d574260c7 in qemu_sem_timedwait (sem=sem@entry=0x7f6d5a1b9248, ms=ms@entry=10000) at util/qemu-thread-posix.c:254
>         rc = <optimized out>
>         ts = {tv_sec = 1447709021, tv_nsec = 21985000}
>         __func__ = "qemu_sem_timedwait"
> #2  0x00007f6d573a98ac in worker_thread (opaque=0x7f6d5a1b91e0) at thread-pool.c:92
>         req = <optimized out>
>         ret = <optimized out>
>         pool = 0x7f6d5a1b91e0
> #3  0x00007f6d55ceadf5 in start_thread (arg=0x7f6ab1dff700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6ab1dff700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140096227505920, 5884348200482620104, 0, 140096227506624, 140096227505920, 26, -5801757560646548792, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #4  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 8 (Thread 0x7f6d44713700 (LWP 52290)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c8b8000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d447129e0, reg_save_area = 0x7f6d447129a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c8b8000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570cc000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c8b8000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c8b8000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d44713700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d44713700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107276433152, 5884348200482620104, 0, 140107276433856, 140107276433152, 140726431086992, -5804032293438111032, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 7 (Thread 0x7f6d42f10700 (LWP 52293)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c8f4000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d42f0f9e0, reg_save_area = 0x7f6d42f0f9a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c8f4000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570c3000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c8f4000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c8f4000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d42f10700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d42f10700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107251255040, 5884348200482620104, 0, 140107251255744, 140107251255040, 140726431086992, -5804046580109950264, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 6 (Thread 0x7f6d45f16700 (LWP 52287)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c878000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d45f159e0, reg_save_area = 0x7f6d45f159a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c878000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570d5000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c878000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c878000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d45f16700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d45f16700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107301611264, 5884348200482620104, 0, 140107301611968, 140107301611264, 140726431086992, -5804035590362381624, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 5 (Thread 0x7f6d43711700 (LWP 52292)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c8e0000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d437109e0, reg_save_area = 0x7f6d437109a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c8e0000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570c6000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c8e0000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c8e0000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d43711700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d43711700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107259647744, 5884348200482620104, 0, 140107259648448, 140107259647744, 140726431086992, -5804047687674641720, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 4 (Thread 0x7f6d43f12700 (LWP 52291)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c8cc000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d43f119e0, reg_save_area = 0x7f6d43f119a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c8cc000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570c9000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c8cc000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c8cc000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d43f12700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d43f12700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107268040448, 5884348200482620104, 0, 140107268041152, 140107268040448, 140726431086992, -5804048786649398584, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 3 (Thread 0x7f6d46717700 (LWP 52286)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c810000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d467169e0, reg_save_area = 0x7f6d467169a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c810000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570d8000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c810000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c810000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d46717700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d46717700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107310003968, 5884348200482620104, 0, 140107310004672, 140107310003968, 140726431086992, -5804036689337138488, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 2 (Thread 0x7f6d45715700 (LWP 52288)):
> #0  0x00007f6d4f8ef257 in ioctl () at ../sysdeps/unix/syscall-template.S:81
> No locals.
> #1  0x00007f6d571f1025 in kvm_vcpu_ioctl (cpu=cpu@entry=0x7f6d5c890000, type=type@entry=44672) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1969
>         ret = <optimized out>
>         arg = <optimized out>
>         ap = {{gp_offset = 16, fp_offset = 0, overflow_arg_area = 0x7f6d457149e0, reg_save_area = 0x7f6d457149a0}}
> #2  0x00007f6d571f10de in kvm_cpu_exec (cpu=cpu@entry=0x7f6d5c890000) at /usr/src/debug/qemu-2.3.0/kvm-all.c:1829
>         run = 0x7f6d570d2000
>         ret = <optimized out>
>         run_ret = <optimized out>
> #3  0x00007f6d571ded7a in qemu_kvm_cpu_thread_fn (arg=0x7f6d5c890000) at /usr/src/debug/qemu-2.3.0/cpus.c:944
>         cpu = 0x7f6d5c890000
>         r = <optimized out>
> #4  0x00007f6d55ceadf5 in start_thread (arg=0x7f6d45715700) at pthread_create.c:308
>         __res = <optimized out>
>         pd = 0x7f6d45715700
>         now = <optimized out>
>         unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140107293218560, 5884348200482620104, 0, 140107293219264, 140107293218560, 140726431086992, -5804034491387624760, -5804071064002379064}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
>         not_first_call = <optimized out>
>         pagesize_m1 = <optimized out>
>         sp = <optimized out>
>         freesize = <optimized out>
> #5  0x00007f6d4f8f81ad in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
> No locals.
> 
> Thread 1 (Thread 0x7f6d570e8c00 (LWP 52281)):
> #0  0x00007f6d52d37be1 in tc_malloc () from /lib64/libtcmalloc.so.4 No symbol table info available.
> #1  0x00007f6d572a4489 in malloc_and_trace (n_bytes=49280) at vl.c:2575
>         ptr = 0x7f6d59a346a0
> #2  0x00007f6d555f947f in g_malloc () from /lib64/libglib-2.0.so.0 No symbol table info available.
> #3  0x00007f6d5560f66e in g_slice_alloc () from /lib64/libglib-2.0.so.0 No symbol table info available.
> #4  0x00007f6d57204ffd in virtio_blk_alloc_request (s=0x7f6d5de1ff40) at /usr/src/debug/qemu-2.3.0/hw/block/virtio-blk.c:33
>         req = <optimized out>
> #5  virtio_blk_get_request (s=0x7f6d5de1ff40) at /usr/src/debug/qemu-2.3.0/hw/block/virtio-blk.c:192
>         req = <optimized out>
> #6  virtio_blk_handle_output (vdev=<optimized out>, vq=<optimized out>) at /usr/src/debug/qemu-2.3.0/hw/block/virtio-blk.c:604
>         s = 0x7f6d5de1ff40
>         __func__ = "virtio_blk_handle_output"
>         mrb = {reqs = {0x7f6d5ca40000, 0x7f6d5db7c000, 0x7f6d5db7c000, 0x0 <repeats 29 times>}, num_reqs = 3, is_write = true}
> #7  0x00007f6d573b76b6 in qemu_iohandler_poll (pollfds=0x7f6d5a1aea00, ret=62, ret@entry=1) at iohandler.c:143
>         revents = 1
> #8  0x00007f6d573b7296 in main_loop_wait (nonblocking=<optimized out>) at main-loop.c:504
>         ret = 1
>         timeout = 4294967295
>         timeout_ns = <optimized out>
> #9  0x00007f6d571b6a4e in main_loop () at vl.c:1818
>         nonblocking = <optimized out>
>         last_io = 0
> #10 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4394
>         i = <optimized out>
>         snapshot = <optimized out>
>         linux_boot = <optimized out>
>         initrd_filename = <optimized out>
>         kernel_filename = <optimized out>
>         kernel_cmdline = <optimized out>
>         boot_order = 0x7f6d57449a67 "cad"
>         boot_once = 0x0
>         cyls = <optimized out>
>         heads = <optimized out>
>         secs = <optimized out>
>         translation = <optimized out>
>         hda_opts = <optimized out>
>         opts = <optimized out>
>         machine_opts = <optimized out>
>         icount_opts = <optimized out>
>         olist = <optimized out>
>         optind = 69
>         optarg = 0x7f6d5a14b3a0 "rhel6.5.0"
>         loadvm = <optimized out>
>         machine_class = <optimized out>
>         cpu_model = <optimized out>
>         vga_model = 0x0
>         qtest_chrdev = <optimized out>
>         qtest_log = <optimized out>
>         pid_file = <optimized out>
>         incoming = <optimized out>
>         show_vnc_port = <optimized out>
>         defconfig = <optimized out>
>         userconfig = 179
>         log_mask = <optimized out>
>         log_file = <optimized out>
>         mem_trace = {malloc = 0x7f6d572a4480 <malloc_and_trace>, realloc = 0x7f6d572a4460 <realloc_and_trace>, free = 0x7f6d572a4450 <free_and_trace>, calloc = 0x0, try_malloc = 0x0, try_realloc = 0x0}
>         trace_events = <optimized out>
>         trace_file = <optimized out>
>         maxram_size = <optimized out>
>         ram_slots = <optimized out>
>         vmstate_dump_file = <optimized out>
>         main_loop_err = 0x0
>         __func__ = "main"
> 
> 
> 
> 
> 
> @ Do you think you're only hitting these crashes on VMs that have been paused because of these space errors?
> Will have a look on that
> 
> Thx Christian
> 
> -----Ursprüngliche Nachricht-----
> Von: Dr. David Alan Gilbert [mailto:dgilbert@redhat.com]
> Gesendet: Dienstag, 17. November 2015 12:36
> An: Grundmann, Christian <Christian.Grundmann@fabasoft.com>
> Cc: 'qemu-devel@nongnu.org' <qemu-devel@nongnu.org>; stefanha@redhat.com
> Betreff: Re: AW: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc
> 
> * Grundmann, Christian (Christian.Grundmann@fabasoft.com) wrote:
> > Hi,
> > 
> > @ Can you please use a 'thread apply all bt full'   the full gives a little more info.
> > 
> > gdb --batch /usr/libexec/qemu-kvm core.52281.1447709011.dump -ex "set pagination off" -ex "thread apply all bt full"
> 
> OK, it doesn't relaly give any more without the debuginfo package mentioned below.
> 
> <snip>
> 
> > @ Also, if you've not already got it installed can you please install the debuginfo package for qemu, it gives a lot more information in backtraces.
> > Sorry it's a ovirt-node System where I can't you yum
> 
> Ah, although perhaps if you took the core dump, onto another machine with matching qemu and debuginfo you should be able to get more detail.
> 
> > @ Does this part always look the same in your backtraces?
> > The most are the same, found one a little bit different :
> > Thread 1 (Thread 0x7f378a0d7c00 (LWP 6658)):
> > #0  0x00007f3785d18353 in
> > tcmalloc::ThreadCache::ReleaseToCentralCache(tcmalloc::ThreadCache::FreeList*, unsigned long, int) () from /lib64/libtcmalloc.so.4 No symbol table info available.
> > #1  0x00007f3785d186b0 in tcmalloc::ThreadCache::Scavenge() () from
> > /lib64/libtcmalloc.so.4 No symbol table info available.
> > #2  0x00007f3785d27057 in tc_free () from /lib64/libtcmalloc.so.4 No 
> > symbol table info available.
> > #3  0x00007f37885e858f in g_free () from /lib64/libglib-2.0.so.0 No 
> > symbol table info available.
> > #4  0x00007f37885fec89 in g_slice_free1 () from
> > /lib64/libglib-2.0.so.0 No symbol table info available.
> > #5  0x00007f378a1f232e in virtio_blk_rw_complete () No symbol table 
> > info available.
> > #6  0x00007f378a39f1ae in bdrv_co_em_bh () No symbol table info 
> > available.
> > #7  0x00007f378a398394 in aio_bh_poll () No symbol table info 
> > available.
> > #8  0x00007f378a3a7409 in aio_dispatch_clients () No symbol table info 
> > available.
> > #9  0x00007f378a39820e in aio_ctx_dispatch () No symbol table info 
> > available.
> > #10 0x00007f37885e299a in g_main_context_dispatch () from
> > /lib64/libglib-2.0.so.0 No symbol table info available.
> > #11 0x00007f378a3a6288 in main_loop_wait () No symbol table info 
> > available.
> > #12 0x00007f378a1a5a4e in main ()
> > No symbol table info available.
> > 
> 
> OK, that's a bit different but interesting....
> 
> > @  1) Was there anything nasty in the /var/log/libvirt/qemu/yourvmname.log ?
> > No nothing abnormal
> > 
> > @  2) Did you hit any IO errors and need to tell the VM to continue after a problem?
> > Ovirt tells me "no Storage space error". Which is something like the disk is growing to fast i think. I use Snapshots so on heavy write the disk has to grow a lot.
> > Sometimes the VM is paused and resumed from ovirt. Sometimes the VM stays offline.
> 
> OK, that's interesting, because you may be hitting the following bug; http://lists.nongnu.org/archive/html/qemu-block/2015-11/msg00585.html
> 
> whose fix coincidentally just got accepted today; it's related to error cases with error=stop which you are using.
> 
> Do you think you're only hitting these crashes on VMs that have been paused because of these space errors?
> 
> >      disk emulation and see if the problem goes away - e.g. virtio-scsi would be a good one to try.
> > 
> > Ok will try that and report
> 
> Thanks,
> 
> Dave
> 
> > 
> > Thx Christian
> > 
> > 
> > -----Ursprüngliche Nachricht-----
> > Von: Dr. David Alan Gilbert [mailto:dgilbert@redhat.com]
> > Gesendet: Dienstag, 17. November 2015 10:59
> > An: Grundmann, Christian <Christian.Grundmann@fabasoft.com>
> > Cc: 'qemu-devel@nongnu.org' <qemu-devel@nongnu.org>; 
> > stefanha@redhat.com
> > Betreff: Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in 
> > libtcmalloc
> > 
> > * Grundmann, Christian (Christian.Grundmann@fabasoft.com) wrote:
> > > Hi,
> > > Dan sent me over to you,
> > > please let me know if i can provide additional informations
> > 
> > Hi Christian,
> >   Thanks for reporting this,
> > 
> > > Softwareversions:
> > > ovirt-node-iso-3.6-0.999.201510221942.el7.centos.iso
> > > 
> > > qemu-img-ev-2.3.0-29.1.el7.x86_64
> > > qemu-kvm-ev-2.3.0-29.1.el7.x86_64
> > > qemu-kvm-common-ev-2.3.0-29.1.el7.x86_64
> > > qemu-kvm-tools-ev-2.3.0-29.1.el7.x86_64
> > > ipxe-roms-qemu-20130517-7.gitc4bce43.el7.noarch
> > > kernel-3.10.0-229.14.1.el7.x86_64
> > > gperftools-libs-2.4-7.el7.x86_64
> > > 
> > > Commandline:
> > > /usr/libexec/qemu-kvm -name myvmname -S -machine 
> > > rhel6.5.0,accel=kvm,usb=off -cpu Westmere -m 7168 -realtime 
> > > mlock=off -smp 2,maxcpus=16,sockets=16,cores=1,threads=1 -uuid
> > > 5b6b8899-5a9d-4c07-a6aa-6171527ad319 -smbios 
> > > type=1,manufacturer=oVirt,product=oVirt
> > > Node,version=3.6-0.999.201510221942.el7.centos,serial=30343536-3138-
> > > 5A
> > > 43-4A34-323630303253,uuid=5b6b8899-5a9d-4c07-a6aa-6171527ad319
> > > -nographic -no-user-config -nodefaults -chardev 
> > > socket,id=charmonitor,path=/var/lib/libvirt/qemu/myvmname.monitor,se
> > > rv er,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc 
> > > base=2015-11-15T20:04:35,driftfix=slew -global 
> > > kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -boot 
> > > strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2
> > > -device
> > > virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 -device
> > > virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
> > > -drive if=none,id=drive-ide0-1-0,readonly=on,format=raw,serial=
> > > -device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0
> > > -drive
> > > file=/rhev/data-center/00000002-0002-0002-0002-0000000000e2/5df61b84
> > > -8
> > > 746-4460-b148-65cc0eb8d29c/images/8202b81d-6191-495f-8c9d-7d90baffae
> > > cf
> > > /d7665e07-1786-4051-aa26-0a3e1c9d2574,if=none,id=drive-virtio-disk0,
> > > fo
> > > rmat=qcow2,serial=8202b81d-6191-495f-8c9d-7d90baffaecf,cache=none,we
> > > rr or=stop,rerror=stop,aio=native -device 
> > > virtio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,
> > > id
> > > =virtio-disk0,bootindex=1 -netdev
> > > tap,fd=39,id=hostnet0,vhost=on,vhostfd=65 -device 
> > > virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:83:a2:0e,bus=pci
> > > .0
> > > ,addr=0x3 -chardev
> > > socket,id=charchannel0,path=/var/lib/libvirt/qemu/channels/5b6b8899-
> > > 5a 9d-4c07-a6aa-6171527ad319.com.redhat.rhevm.vdsm,server,nowait
> > > -device
> > > virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=cha
> > > nn el0,name=com.redhat.rhevm.vdsm -chardev
> > > socket,id=charchannel1,path=/var/lib/libvirt/qemu/channels/5b6b8899-
> > > 5a 9d-4c07-a6aa-6171527ad319.org.qemu.guest_agent.0,server,nowait
> > > -device
> > > virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=cha
> > > nn
> > > el1,name=org.qemu.guest_agent.0 -device
> > > cirrus-vga,id=video0,bus=pci.0,addr=0x2 -device
> > > virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 -msg timestamp=on
> > > 
> > > Stack Trace:
> > > 
> > > gdb --batch /usr/libexec/qemu-kvm core.14750.1447544080.dump -ex "set pagination off" -ex "thread apply all bt"
> > 
> > Can you please use a 'thread apply all bt full'   the full gives a little more info.
> > Also, if you've not already got it installed can you please install the debuginfo package for qemu, it gives a lot more information in backtraces.
> > 
> > > Thread 1 (Thread 0x7fa8b16afc00 (LWP 14750)):
> > > #0  0x00007fa8ad2febe1 in tc_malloc () from /lib64/libtcmalloc.so.4
> > > #1  0x00007fa8b186b489 in malloc_and_trace ()
> > > #2  0x00007fa8afbc047f in g_malloc () from /lib64/libglib-2.0.so.0
> > > #3  0x00007fa8afbd666e in g_slice_alloc () from
> > > /lib64/libglib-2.0.so.0
> > > #4  0x00007fa8b17cbffd in virtio_blk_handle_output ()
> > > #5  0x00007fa8b197e6b6 in qemu_iohandler_poll ()
> > > #6  0x00007fa8b197e296 in main_loop_wait ()
> > > #7  0x00007fa8b177da4e in main ()
> > 
> > Does this part always look the same in your backtraces?
> > The segfault in tc_malloc is probably due to a heap corruption, or double free or similar - although it can be a bit tricky to find out what did it, since the corruption might have happened a bit before the place it crashed.
> > 
> > Some other ideas:
> >   1) Was there anything nasty in the /var/log/libvirt/qemu/yourvmname.log ?
> >   2) Did you hit any IO errors and need to tell the VM to continue after a problem?
> >   3) If this is pretty repeatable, then it would be interesting to try changing to a different
> >      disk emulation and see if the problem goes away - e.g. virtio-scsi would be a good one to try.
> > 
> > Dave
> > > 
> > > 
> > > Thx Christian
> > > 
> > > -----Ursprüngliche Nachricht-----
> > > Von: Dan Kenigsberg [mailto:danken@redhat.com]
> > > Gesendet: Freitag, 13. November 2015 20:00
> > > An: Grundmann, Christian <Christian.Grundmann@fabasoft.com>
> > > Cc: 'users@ovirt.org' <users@ovirt.org>
> > > Betreff: Re: [ovirt-users] Segmentation fault in libtcmalloc
> > > 
> > > On Fri, Nov 13, 2015 at 07:56:14AM +0000, Grundmann, Christian wrote:
> > > > Hi,
> > > > i am using "ovirt-node-iso-3.6-0.999.201510221942.el7.centos.iso" 
> > > > (is there something better to use?) fort he nodes, and have random 
> > > > crashes of VMs The dumps are always the Same
> > > > 
> > > > gdb --batch /usr/libexec/qemu-kvm core.45902.1447199164.dump 
> > > > [Thread debugging using libthread_db enabled] Using host 
> > > > libthread_db library "/lib64/libthread_db.so.1".
> > > > Core was generated by `/usr/libexec/qemu-kvm -name vmname -S -machine rhel6.5.0,accel=kvm,usb=o'.
> > > > Program terminated with signal 11, Segmentation fault.
> > > > #0  0x00007f0c559c4353 in
> > > > tcmalloc::ThreadCache::ReleaseToCentralCache(tcmalloc::ThreadCache::
> > > > Fr eeList*, unsigned long, int) () from /lib64/libtcmalloc.so.4
> > > > 
> > > > 
> > > > Didn't have the Problem with 3.5 el6 nodes, so don't no if ist
> > > > centos7 or 3.6
> > > 
> > > Due to the low-leveled-ness of the problem, I'd guess it's a qemu//lib64/libtcmalloc malloc bug, and not directly related to ovirt.
> > > 
> > > Please report the precise version of qemu,kernel,libvirt and gperftools-libs to qemu-devel mailing list and the complete stack trace and qemu command line, if possible.
> > > 
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK