From: Julian Wiedmann <jwi@xxxxxxxxxxxxx> commit ac6639cd3db607d386616487902b4cc1850a7be5 upstream. Current code sets the dsci to 0x00000080. Which doesn't make any sense, as the indicator area is located in the _left-most_ byte. Worse: if the dsci is the _shared_ indicator, this potentially clears the indication of activity for a _different_ device. tiqdio_thinint_handler() will then have no reason to call that device's IRQ handler, and the device ends up stalling. Fixes: d0c9d4a89fff ("[S390] qdio: set correct bit in dsci") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx> Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/s390/cio/qdio_thinint.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/s390/cio/qdio_thinint.c +++ b/drivers/s390/cio/qdio_thinint.c @@ -80,7 +80,6 @@ void tiqdio_add_input_queues(struct qdio mutex_lock(&tiq_list_lock); list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list); mutex_unlock(&tiq_list_lock); - xchg(irq_ptr->dsci, 1 << 7); } void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)