When the underlying file system returns an error from the chdir call, and this happens while the server is shutting down, this is reported as ABNORMAL_SHUTDOWN and triggers a panic and a coredump. As the log already contains an error message about the failing system call, the coredump is not necessary for troubleshooting and should be avoided in this case.
Created attachment 13873 [details] Patches for 4.6
Created attachment 13874 [details] Patches for 4.7
Re-assigning to Karolin for inclusion in 4.7.next, 4.6.next.
(In reply to Jeremy Allison from comment #3) Pushed to autobuild-v4-{7,6}-test.
(In reply to Karolin Seeger from comment #4) Pushed to both branches. Closing out bug report. Thanks!