Core dump with all the latest changes:

Mar 14 07:22:57 spectre dovecot: master: service(auth): child 1841 killed with signal 11 (core dumped)

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warning: Can't read pathname for load map: Input/output error. Reading symbols from /usr/lib/dovecot/libdovecot.so.0...Reading symbols from /usr/lib/debug/usr/lib/dovecot/libdovecot.so.0.0.0...done. done. Loaded symbols for /usr/lib/dovecot/libdovecot.so.0 Reading symbols from /lib/libcrypt.so.1...done. Loaded symbols for /lib/libcrypt.so.1 Reading symbols from /lib/libpam.so.0...done. Loaded symbols for /lib/libpam.so.0 Reading symbols from /lib/libdl.so.2...done. Loaded symbols for /lib/libdl.so.2 Reading symbols from /lib/librt.so.1...done. Loaded symbols for /lib/librt.so.1 Reading symbols from /lib/libc.so.6...done. Loaded symbols for /lib/libc.so.6 Reading symbols from /lib/ld-linux-x86-64.so.2...done. Loaded symbols for /lib64/ld-linux-x86-64.so.2 Reading symbols from /lib/libpthread.so.0...done. Loaded symbols for /lib/libpthread.so.0 Core was generated by `dovecot/auth'. Program terminated with signal 11, Segmentation fault. [New process 1841] #0 aqueue_count (aqueue=0x0) at aqueue.c:122 122 aqueue.c: No such file or directory. in aqueue.c (gdb) bt full #0 aqueue_count (aqueue=0x0) at aqueue.c:122 area_size = 6583600 #1 0x000000000041010b in auth_request_handler_flush_failures (flush_all=true) at auth-request-handler.c:569 auth_requests = <value optimized out> auth_request = <value optimized out> i = <value optimized out> count = <value optimized out> __PRETTY_FUNCTION__ = "auth_request_handler_flush_failures" #2 0x00000000004101fe in auth_request_handler_deinit () at auth-request-handler.c:608 No locals. #3 0x000000000040a136 in auth_deinit (_auth=0x0) at auth.c:229 auth = (struct auth *) 0x644df8 passdb = <value optimized out> userdb = (struct auth_userdb *) 0x0 #4 0x000000000040a19f in auths_deinit () at auth.c:291 auth = (struct auth **) 0x642010 i = <value optimized out> #5 0x00000000004147fe in main (argc=1, argv=0x639370) at main.c:115 c = <value optimized out>

Regards Thomas