FreeBSD 11.0-CURRENT #0 r295763. Seems like on of my flash drives became buggy: sometimes it work well, sometimes it gives read/write errors. The problem is, however, how FreeBSD handles umounting of this device. After issuing `umount' it tries to write on drive infinitely (waited for half an hour), and if the drive is detached the system panics. No backtrace yet, but may try to reproduce and gather more info.
Created attachment 168817 [details] Log