== writer: 12-byte TPM-ish command to /dev/uafsim0 (blocks ~5s in transmit) ==
== firing detach (== kldunload tpm while transmit in flight) ==
hw.uafsim_detach: 0WRITER DONE rc=0
 -> 0
== detach returned; waiting for delayed effects (callout fires 500ms after writer returns) ==
== SURVIVED? (no panic expected to reach here) ==
sio2: can't drain, serial port might not exist, disabling
hpt27xx: no controller detected.
CAM: Configuring 2 busses
CAM: finished configuring all busses
cd0 at ata1 bus 0 target 0 lun 0
cd0: <QEMU QEMU DVD-ROM 2.5+> Removable CD-ROM SCSI-0 device 
cd0: 16.000MB/s transfers
cd0: Attempt to query device size failed: NOT READY, Medium not present
Mounting root from hammer2:vbd0s1d
hammer2_mount: root devstr="vbd0s1d"
hammer2_mount: device="vbd0s1d" label="ROOT" rdonly=1
hammer2_ondisk: "/dev/vbd0s1d" zone=3 id=0 offset=0x0000000000000000 size=0x000000063f000000
hammer2_mount: hmp=0xfffff8008fae0000 pmp=0xfffff80090280000
DMA space used: 13580k, remaining available: 131072k
Mounting devfs
hammer2_mount: "vbd0s1d": no recovery needed
hammer2: enable read/write
HAMMER2: VOLDATA DUMP
HAMMER2: INITIATE SPANs
swap low/high-water marks set to 41940/62910
uafsim: loaded; write >=10 bytes to /dev/uafsim0 then sysctl hw.uafsim_detach=1
uafsim: [detach] lockstatus(dev_lock)=8 (1 == LK_EXCLUSIVE held by writer)
uafsim: [detach] calling stock tpm20_release() with dev_lock HELD elsewhere
uafsim: [detach] tpm20_release() returned; lockuninit assert did NOT fire
uafsim: [detach] softc freed + sprayed; writer still asleep inside transmit