Collect core dump with shared memory of running process

Question

Core dump collects only process space but not the shared memory which is created for Inter-process communication. How can I make core dump to include shared memory of running process too?

Answer 1

Set the core file filter in /proc/PID/coredump_filter per http://man7.org/linux/man-pages/man5/core.5.html:

Controlling which mappings are written to the core dump

   Since kernel 2.6.23, the Linux-specific /proc/PID/coredump_filter
   file can be used to control which memory segments are written to the
   core dump file in the event that a core dump is performed for the
   process with the corresponding process ID.

   The value in the file is a bit mask of memory mapping types (see
   mmap(2)).  If a bit is set in the mask, then memory mappings of the
   corresponding type are dumped; otherwise they are not dumped.  The
   bits in this file have the following meanings:

       bit 0  Dump anonymous private mappings.
       bit 1  Dump anonymous shared mappings.
       bit 2  Dump file-backed private mappings.
       bit 3  Dump file-backed shared mappings.
       bit 4 (since Linux 2.6.24)
              Dump ELF headers.
       bit 5 (since Linux 2.6.28)
              Dump private huge pages.
       bit 6 (since Linux 2.6.28)
              Dump shared huge pages.
       bit 7 (since Linux 4.4)
              Dump private DAX pages.
       bit 8 (since Linux 4.4)
              Dump shared DAX pages.

   By default, the following bits are set: 0, 1, 4 (if the
   CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS kernel configuration option is
   enabled), and 5.  This default can be modified at boot time using the
   coredump_filter boot option.