When diag204 busy-indiciation facility is installed and diag204 is returning busy, hypfs diag204 handler now does an interruptable busy wait until diag204 is no longer busy. If there is a signal pending, call would be restarted with -ERESTARTSYSCALL, except for fatal signals. Acked-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Tobias Huschle <huschle@linux.ibm.com> Signed-off-by: Mete Durlu <meted@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>