crash> bt/a ffffb3a0a0fe71a0
trace: pid 0 lid 62 at 0xffff80012cb5acd0
sleepq_block() at sleepq_block+0x115
kpause() at kpause+0xed
scsibusdetach() at scsibusdetach+0x3d
config_detach() at config_detach+0x121
umass_detach() at umass_detach+0xa7
config_detach() at config_detach+0x121
usb_disconnect_port() at usb_disconnect_port+0x192
uhub_explore() at uhub_explore+0x221
usb_discover() at usb_discover+0x8c
usb_event_thread() at usb_event_thread+0x24e
crash> bt
crash> bt/a ffffb3a0a0fe71a0
trace: pid 0 lid 62 at 0xffff80012cb5acd0
sleepq_block() at sleepq_block+0x115
kpause() at kpause+0xed
scsibusdetach() at scsibusdetach+0x3d
config_detach() at config_detach+0x121
umass_detach() at umass_detach+0xa7
config_detach() at config_detach+0x121
usb_disconnect_port() at usb_disconnect_port+0x192
uhub_explore() at uhub_explore+0x221
usb_discover() at usb_discover+0x8c
usb_event_thread() at usb_event_thread+0x24e
crash> bt/a ffffb3a39bd874c0
trace: pid 0 lid 88 at 0xffff80012c705d50
sleepq_block() at sleepq_block+0xaa
cv_wait() at cv_wait+0x137
scsipi_execute_xs() at scsipi_execute_xs+0x22a
scsipi_command() at scsipi_command+0xa8
scsipi_inquire() at scsipi_inquire+0x76
scsi_probe_bus() at scsi_probe_bus+0x264
scsibus_discover_thread() at scsibus_discover_thread+0x7f