$ vm.sh run_root 'dd if=/dev/zero of=/tmp/stress bs=1m count=512; dd if=/tmp/stress of=/dev/null bs=1m; dmesg | grep -ciE "taskqueue timeout|TIMEOUT.*retry|ata.*timeout"'
536870912 bytes transferred in 0.691949 secs (775882704 bytes/sec)
536870912 bytes transferred in 0.084017 secs (6390041612 bytes/sec)
0
DANGER_MSGS_ABOVE
# -> the emulated channel never approaches the 40 s (4x timeout) zombie
#    precondition; no in-guest stall dial exists. Trigger not stageable.