Getting eternal waiting while opening 6 GB core file

Hi. My program crashed while being launched by another person in their
private environment (so it is not a good option to re-run app under
gdb).
They gave me an app binary which produced crash, and a core file. Core
file size is ~6 GB, i don't know if it matters.
I open it as "gdb app-binary core-file"

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Reading symbols from /tmp/tvipdrm_scrambler...done.

warning: core file may not match specified executable file.
[New LWP 13022]
...
[New LWP 13061]

warning: Can't read pathname for load map: Ошибка ввода/вывода.

warning: .dynamic section for "/lib/libpthread.so.0" is not at the
expected address (wrong library or version mismatch?)

warning: .dynamic section for "/lib/libdl.so.2" is not at the expected
address (wrong library or version mismatch?)

warning: .dynamic section for "/lib/librt.so.1" is not at the expected
address (wrong library or version mismatch?)

warning: .dynamic section for "/lib/libm.so.6" is not at the expected
address (wrong library or version mismatch?)

warning: .dynamic section for "/lib/libc.so.6" is not at the expected
address (wrong library or version mismatch?)

warning: .dynamic section for "/lib64/ld-linux-x86-64.so.2" is not at
the expected address (wrong library or version mismatch?)

warning: Could not load shared library symbols for 2 libraries, e.g.
/usr/lib/libstdc++.so.6.
Use the "info sharedlibrary" command to see the complete listing.
Do you need "set solib-search-path" or "set sysroot"?


And there it hangs forever. I see gdb process loads one processor core
for ~100%.
"ps axf" shows gdb process state "R+".
I thought it's ok, because i have large file, so i left it to work.
But it did not show any progress in ~8 hours.

So i attached to gdb process with gdb. See backtrace below:

(gdb) info threads
  Id   Target Id         Frame
* 1    Thread 0x7f1283f6f700 (LWP 4307) "gdb" 0x00007f1282933af0 in
__lseek_nocancel () from /lib64/libc.so.6
(gdb) bt
#0  0x00007f1282933af0 in __lseek_nocancel () from /lib64/libc.so.6
#1  0x00007f12828beffd in _IO_file_seekoff () from /lib64/libc.so.6
#2  0x00007f12828bcf32 in fseeko64 () from /lib64/libc.so.6
#3  0x000000000066c467 in bfd_seek ()
#4  0x0000000000671819 in _bfd_generic_get_section_contents ()
#5  0x00000000005b1ee8 in section_table_xfer_memory_partial ()
#6  0x000000000052b367 in core_xfer_partial ()
#7  0x00000000005a667d in memory_xfer_partial_1 ()
#8  0x00000000005a6c6f in target_xfer_partial ()
#9  0x00000000005a6509 in target_read ()
#10 0x00000000005a6fd0 in target_read_memory ()
#11 0x000000000048fad1 in ps_xfer_memory ()
#12 0x00007f1281f25a93 in td_thr_get_info () from /lib64/libthread_db.so.1
#13 0x00000000004909b1 in find_new_threads_callback ()
#14 0x00007f1281f255da in iterate_thread_list () from /lib64/libthread_db.so.1
#15 0x00007f1281f2573e in td_ta_thr_iter () from /lib64/libthread_db.so.1
#16 0x0000000000490262 in find_new_threads_once ()
#17 0x0000000000490581 in thread_db_find_new_threads_2 ()
#18 0x0000000000492749 in thread_db_find_new_threads_silently ()
#19 0x0000000000492b7b in try_thread_db_load ()
#20 0x000000000049341d in check_for_thread_db ()
#21 0x00000000005b6215 in observer_notify_new_objfile ()
#22 0x000000000055d240 in symbol_file_add_with_addrs_or_offsets.constprop.17 ()
#23 0x000000000064e449 in solib_read_symbols ()
#24 0x000000000064e85b in solib_add ()
#25 0x0000000000569580 in post_create_inferior ()
#26 0x000000000052bdcb in core_open ()
#27 0x000000000058164f in catch_command_errors ()
#28 0x0000000000583a6b in captured_main ()
#29 0x000000000058158b in catch_errors ()
#30 0x0000000000583bf4 in gdb_main ()
#31 0x0000000000456bbe in main ()
(gdb)


Any ideas how to succeed working with that core?

--
Andrey Utkin