Is it possible to get the backtrace for a LoR from any of the system logs or anything like that, after the fact? Especially after rebooting into a non-debug kernel? I compiled a custom kernel for our ZFS boxes that have been locking up on me lately, adding INVARIANTS and WITNESS. But, to be safe, I booted the debug kernel using nextboot on Friday. The boxes locked up over the weekend, and we restarted, reverting them back to the non-debug kernel. Going through /var/log/messages, I see a couple LoRs that aren't listed on http://ipv4.sources.zabbadoz.net/freebsd/lor.html However, as I'm not running the debug kernel anymore, I can't go through sysctl to grab the backtrace for it. Is there any other way to get the info? Is there anyway to configure the system to log the backtrace to a file? Here's the info from /var/log/messages, which I'm guessing is not enough to track down the cause of the LoR: lock order reversal: 1st 0xfffffe0019415098 zfs (zfs) @ /usr/src/sys/modules/zfs/../../cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c:1704 2nd 0xfffffe00191669f8 ufs (ufs) @ /usr/src/sys/kern/vfs_syscalls.c:1665 lock order reversal: 1st 0xfffffe00194d0eb8 rtentry (rtentry) @ /usr/src/sys/net/route.c:374 2nd 0xfffffe000adb2bc0 if_afdata (if_afdata) @ /usr/src/sys/netinet6/scope6.c:417 System info: FreeBSD betadrive.sd73.bc.ca 9.0-STABLE FreeBSD 9.0-STABLE #0 r234466: Fri Apr 20 10:57:30 PDT 2012 root@betadrive.sd73.bc.ca:/usr/obj/usr/src/sys/ZFSHOST90 amd64 -- Freddie Cash fjwcash@gmail.com