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Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc |
Date: |
Tue, 17 Nov 2015 14:42:26 +0000 |
User-agent: |
Mutt/1.5.24 (2015-08-30) |
* Grundmann, Christian (address@hidden) 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 (address@hidden, obj=0x7f5d07f905a0,
> address@hidden "stats", address@hidden) 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 (address@hidden, obj=0x7f5d07f90650, address@hidden
> "parent", address@hidden) 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 (address@hidden, obj=0x7f5d07c67a50,
> address@hidden, address@hidden) at qapi-visit.c:1644
> err = 0x0
> #16 0x00007f5d03ebf760 in visit_type_BlockStatsList (m=0x7f5d061fdea0,
> address@hidden, address@hidden "unused", address@hidden) 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 (address@hidden, ch=<optimized
> out>, address@hidden) 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: address@hidden [mailto:address@hidden Im Auftrag von Grundmann, Christian
> Gesendet: Dienstag, 17. November 2015 15:12
> An: 'Dr. David Alan Gilbert' <address@hidden>
> Cc: 'address@hidden' <address@hidden>; address@hidden
> 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 (address@hidden <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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden)
> 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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 (address@hidden, address@hidden) 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 (address@hidden) 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, address@hidden) 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:address@hidden
> Gesendet: Dienstag, 17. November 2015 12:36
> An: Grundmann, Christian <address@hidden>
> Cc: 'address@hidden' <address@hidden>; address@hidden
> Betreff: Re: AW: [Qemu-devel] WG: [ovirt-users] Segmentation fault in
> libtcmalloc
>
> * Grundmann, Christian (address@hidden) 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:address@hidden
> > Gesendet: Dienstag, 17. November 2015 10:59
> > An: Grundmann, Christian <address@hidden>
> > Cc: 'address@hidden' <address@hidden>;
> > address@hidden
> > Betreff: Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in
> > libtcmalloc
> >
> > * Grundmann, Christian (address@hidden) 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:address@hidden
> > > Gesendet: Freitag, 13. November 2015 20:00
> > > An: Grundmann, Christian <address@hidden>
> > > Cc: 'address@hidden' <address@hidden>
> > > 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 / address@hidden / Manchester, UK
> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK
>
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK
- [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Grundmann, Christian, 2015/11/16
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Dr. David Alan Gilbert, 2015/11/17
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Grundmann, Christian, 2015/11/17
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Dr. David Alan Gilbert, 2015/11/17
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Grundmann, Christian, 2015/11/17
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Grundmann, Christian, 2015/11/17
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc,
Dr. David Alan Gilbert <=
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Grundmann, Christian, 2015/11/19
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Paolo Bonzini, 2015/11/19
- Re: [Qemu-devel] WG: [ovirt-users] Segmentation fault in libtcmalloc, Dr. David Alan Gilbert, 2015/11/20