I recently upgraded from FreeNAS 11 to TrueNAS 12.0 and have noticed that SMBD keeps crashing every few minutes under very minimal load. Possibly relevant logs:
/var/log/samba4/log.smbd
[2020/12/14 11:05:37.345113, 0] ../../lib/util/fault.c:79(fault_report)
===============================================================
[2020/12/14 11:05:37.345206, 0] ../../lib/util/fault.c:80(fault_report)
INTERNAL ERROR: Signal 11 in pid 39227 (4.12.9)
If you are running a recent Samba version, and if you think this problem is not yet fixed in the latest versions, please consider reporting this bug, see https://wiki.samba.org/index.php/Bug_Reporting
[2020/12/14 11:05:37.345290, 0] ../../lib/util/fault.c:86(fault_report)
===============================================================
[2020/12/14 11:05:37.345345, 0] ../../source3/lib/util.c:830(smb_panic_s3)
PANIC (pid 39227): internal error
[2020/12/14 11:05:37.347410, 0] ../../lib/util/fault.c:265(log_stack_trace)
BACKTRACE: 6 stack frames:
#0 0x801296217 <log_stack_trace+0x37> at /usr/local/lib/samba4/libsamba-util.so.0
#1 0x802f9b656 <smb_panic_s3+0x56> at /usr/local/lib/samba4/libsmbconf.so.0
#2 0x801296007 <smb_panic+0x17> at /usr/local/lib/samba4/libsamba-util.so.0
#3 0x8012963ee <log_stack_trace+0x20e> at /usr/local/lib/samba4/libsamba-util.so.0
#4 0x801295fe9 <fault_setup+0x59> at /usr/local/lib/samba4/libsamba-util.so.0
#5 0x8099dbc20 <_pthread_sigmask+0x530> at /lib/libthr.so.3
[2020/12/14 11:05:37.347698, 0] ../../source3/lib/dumpcore.c:315(dump_core)
dumping core in /var/db/system/cores
/var/log/messages
Dec 14 10:42:54 threenas kernel: pid 38893 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:42:59 threenas kernel: pid 38894 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:43:07 threenas kernel: pid 38895 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:27 threenas kernel: pid 38906 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:37 threenas kernel: pid 38974 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:49 threenas kernel: pid 38975 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 11:04:45 threenas kernel: pid 39193 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 11:05:37 threenas kernel: pid 39227 (smbd), jid 0, uid 0: exited on signal 6
/var/log/samba4/log.smbd
[2020/12/14 11:05:37.345113, 0] ../../lib/util/fault.c:79(fault_report)
===============================================================
[2020/12/14 11:05:37.345206, 0] ../../lib/util/fault.c:80(fault_report)
INTERNAL ERROR: Signal 11 in pid 39227 (4.12.9)
If you are running a recent Samba version, and if you think this problem is not yet fixed in the latest versions, please consider reporting this bug, see https://wiki.samba.org/index.php/Bug_Reporting
[2020/12/14 11:05:37.345290, 0] ../../lib/util/fault.c:86(fault_report)
===============================================================
[2020/12/14 11:05:37.345345, 0] ../../source3/lib/util.c:830(smb_panic_s3)
PANIC (pid 39227): internal error
[2020/12/14 11:05:37.347410, 0] ../../lib/util/fault.c:265(log_stack_trace)
BACKTRACE: 6 stack frames:
#0 0x801296217 <log_stack_trace+0x37> at /usr/local/lib/samba4/libsamba-util.so.0
#1 0x802f9b656 <smb_panic_s3+0x56> at /usr/local/lib/samba4/libsmbconf.so.0
#2 0x801296007 <smb_panic+0x17> at /usr/local/lib/samba4/libsamba-util.so.0
#3 0x8012963ee <log_stack_trace+0x20e> at /usr/local/lib/samba4/libsamba-util.so.0
#4 0x801295fe9 <fault_setup+0x59> at /usr/local/lib/samba4/libsamba-util.so.0
#5 0x8099dbc20 <_pthread_sigmask+0x530> at /lib/libthr.so.3
[2020/12/14 11:05:37.347698, 0] ../../source3/lib/dumpcore.c:315(dump_core)
dumping core in /var/db/system/cores
/var/log/messages
Dec 14 10:42:54 threenas kernel: pid 38893 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:42:59 threenas kernel: pid 38894 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:43:07 threenas kernel: pid 38895 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:27 threenas kernel: pid 38906 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:37 threenas kernel: pid 38974 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 10:47:49 threenas kernel: pid 38975 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 11:04:45 threenas kernel: pid 39193 (smbd), jid 0, uid 0: exited on signal 6
Dec 14 11:05:37 threenas kernel: pid 39227 (smbd), jid 0, uid 0: exited on signal 6