From the logs, I am unable to determine how rbd-mirror started an image trim operation:

 6: (librbd::operation::C_CopyupObject<librbd::ImageCtx>::send()+0x110) [0x7f7556c7b6c0]

There are 24 instances of this crash over the past day. Per "yum history", it appears the incorrect ceph-debuginfo package (ceph-debuginfo-1:9.2.1-0.el7.x86_64) was installed during all but the most recent crash, so it's quite possible that this is a false backtrace.

Need system properly configured to generate core file -- I'll keep gdb attached but it hasn't crashed in several hours whereas before it was crashing nearly every hour. If that backtrace is correct, there should be lots of log messages supporting that fact but there are none.

Unable to reproduce the same in the latest build.
ceph version 10.2.2-15.el7cp

Marking it as Verified.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-1755.html