what does "deleted" mean in segfault error in syslog?

Question

Mar 21 15:59:56 loong kernel: [ 364.376809] communicator[5399]: segfault at 273c6 ip 00000000000273c6 sp 00007fc0c8a15818 error 14 in communicator (deleted)[400000+29000]

Answer 1

When you delete a file currently in use, it gets marked deleted and is no longer listed but can still be used until the process currently having it open closes it.

$ cat > foo &
[1] 13566
$ rm foo
[1]+  Stopped                 cat > foo
$ ls foo
ls: cannot access foo: No such file or directory
$ ls -l /proc/13566/fd
total 0
lrwx------ 1 pterjan pterjan 64 Mar 22 21:17 0 -> /dev/pts/4
l-wx------ 1 pterjan pterjan 64 Mar 22 21:17 1 -> /tmp/foo (deleted)
lrwx------ 1 pterjan pterjan 64 Mar 22 21:17 2 -> /dev/pts/4

So, the communicator executable had been deleted before it crashed (maybe it was replaced by a new one during an update, or it was just deleted).