Error caused with pull request merge, which occurs everytime the merge commit is accessed

After a pull request is merged, we receive the following error:
'/usr/bin/git rev-list --format=%H%x02%P%x02%aN%x02%aE%x02%at%n%B%n%x03END%x04 --no-walk a489ce176fc26d322863e531e6f947df79fb6c02 a489ce176fc26d322863e531e6f947df79fb6c02^@ --' exited with code 141'

The pull request gets closed as merged, but every time the merge commit is accessed via Stash (e.g. commits navigation, branch navigation, pull request creation) the same error will be displayed.

This issue was seen once about a week and a half ago and could not be reproduced. Several days later (Friday February 27), we had hardware upgraded and had a slight issue restarting the database due to some incorrect permissions, but after successful db restart and Stash restart, we were able to pass sanity testing (create branches, pull requests and merge) and no issues were reported from teams using it. But today we had to bring Stash down for a minor config change. A project was previously setup for "squash" merge strategy for pull requests (owned by same team that reported the problem the previous week and a half). We brought Stash down and deleted one line for the "squash" merge strategy for the one project (they wanted the default of "no-ff"). After restarting, we started our sanity testing in a test project (not the same as the project that we removed the "squash" merge strategy for). We started getting the error above every time on a pull request merge that had a merge commit created and whenever that merge commit is accessed. This is happening every time now!

This appears like it could be related to STASH-6972... We have not had a chance to upgrade to 3.6.1.. also i wasn't sure if this was happening every time for the person that reported STASH-6972.

I also built and installed git 2.3 (this was mentioned in STASH-6972 as working for another team) and restarted with that set as the version for the "atlstash" user. Still no luck...