(#219074 is similar in subject, but stack trace is different).

Today I wanted to record a CDRW, I inserted a non empty one (which I intended to blank) and my system crashed.

#0  doadump (textdump=<value optimized out>) at pcpu.h:233
	in pcpu.h
(kgdb) #0  doadump (textdump=<value optimized out>) at pcpu.h:233
#1  0xffffffff805755db in kern_reboot (howto=260)
    at /usr/src/sys/kern/kern_shutdown.c:383
#2  0xffffffff80575a01 in vpanic (fmt=<value optimized out>, 
    ap=<value optimized out>) at /usr/src/sys/kern/kern_shutdown.c:776
#3  0xffffffff80575843 in panic (fmt=<value optimized out>)
    at /usr/src/sys/kern/kern_shutdown.c:707
#4  0xffffffff807f516f in trap_fatal (frame=0xfffffe01f3916a60, eva=8)
    at /usr/src/sys/amd64/amd64/trap.c:875
#5  0xffffffff807f51c9 in trap_pfault (frame=0xfffffe01f3916a60, usermode=0)
    at pcpu.h:233
#6  0xffffffff807f49c7 in trap (frame=0xfffffe01f3916a60)
    at /usr/src/sys/amd64/amd64/trap.c:415
#7  0xffffffff807d668c in calltrap ()
    at /usr/src/sys/amd64/amd64/exception.S:231
#8  0xffffffff804ecd4e in g_dev_orphan (cp=0xfffff8002d1b9700)
    at /usr/src/sys/geom/geom_dev.c:761
#9  0xffffffff804f5081 in g_resize_provider_event (arg=<value optimized out>, 
    flag=<value optimized out>) at /usr/src/sys/geom/geom_subr.c:631
#10 0xffffffff804f04ce in g_run_events ()
    at /usr/src/sys/geom/geom_event.c:264
#11 0xffffffff80541a63 in fork_exit (
    callout=0xffffffff804f2890 <g_event_procbody>, arg=0x0, 
    frame=0xfffffe01f3916c00) at /usr/src/sys/kern/kern_fork.c:1054
#12 0xffffffff807d75be in fork_trampoline ()
    at /usr/src/sys/amd64/amd64/exception.S:960
#13 0x0000000000000000 in ?? ()
Current language:  auto; currently minimal
(kgdb) 


Possibly devd or some other component (from XFCE?) tried to access the disk, alhough I didn't ask to mount it in any way.

Notice this is my first multi-user boot after the upgrade to 11.2-RELEASE-p11: this might be related or not to FreeBSD-SA-19:11.cd_ioctl, but it never happened before.