Never saw that error before. Yes, running older kernel, maybe all is fine now.
Machine froze after "sd0: cache synchronization failed" sd0 is USB-connected 4T disk
Was able to send Break via the PuTTY session, serial console. Note debugger prompt camp up; I futzed around with ? and 'help' and then, without typing anything, machine rebooted. (I was trying to get a stack trace)
CONSOLE:
May 11 11:30:31 S sshd[23397]: error: maximum authentication attempts exceeded for root from 106.118.88.231 port 41408 ssh2 [preauth]
sd0(umass0:0:0:0): generic HBA error
sd0: cache synchronization failed
Stopped in pid 0.2 (system) at netbsd:cpu_Debugger+0x4: bx r14
db{0}> ?
Bad character
?
db{0}> help
b delete match search w
break dmesg next set watch
bt dwatch p show whatis
c examine print sifting write
call exit ps step x
callout help quit sync
continue kill reboot trace
d machine s until
db{0}>
NetBSD/evbarm (rpi) booting ...
[ Kernel symbol table missing! ]
Copyright (c) ... <redacted> ...
NetBSD 8.0 (RPI2) #0: Tue Jul 17 14:59:51 UTC 2018
mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/evbarm/compile/RPI2
total memory = 948 MB
avail memory = 928 MB
Filesystem 1G-blocks Used Avail %Cap Mounted on
/dev/ld0a 28 3 24 11% /
/dev/ld0e 0 0 0 16% /boot
/dev/sd0 3668 678 2806 19% /c
/dev/sd1e 58 41 14 74% /d
kernfs 0 0 0 100% /kern
ptyfs 0 0 0 100% /dev/pts
procfs 0 0 0 100% /proc
tmpfs 0 0 0 0% /tmp
-----------------
THEN, all data/programs in the subdirectory on /c that I was working on disappeared upon reboot (!). Stuff that had been there for at least a few days. fsck -f /dev/sd0 produced no errors.
/dev/ld0a / ffs rw,log,noatime 1 1
/dev/ld0b none swap sw 0 0
/dev/ld0e /boot msdos rw 1 1
/dev/sd0 /c ffs rw,log,noatime 1 1
/dev/sd1e /d ffs rw,log,noatime 1 1
kernfs /kern kernfs rw
ptyfs /dev/pts ptyfs rw
procfs /proc procfs rw
tmpfs /tmp tmpfs rw,-m1777,-sram%25
I've since removed 'noatime'.