The stdout stream is not line-buffered, which means that occasionally the
chunk/Buffer of data that comes in immediately after we run the commands may be:
~% chmod +x /mnt/test-i386
~% /mnt/test-i386 > /mnt/result
~% echo test fini''shed
test finished
~%
Note how the data ends with the prompt, not in "test finished\n" - this will
cause the test to run indefinitely.
Recently distributions started disabling the CONFIG_MODIFY_LDT_SYSCALL
kernel config, breaking parts of the qemu test. qemu is very suitable to
run these tests in the same configuration as v86 (booting from
linux3.iso, exchanging files using 9p fs and controlling via serial
console).
