A "powernv" machine type defines an ISA bus but it does not add any DMA controller to it so it is possible to hit assert(fdctrl->dma) by adding "-machine powernv -device isa-fdc".
This replaces assert() with an error message. Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru> --- Is it a must for ISA to have DMA controllers? --- hw/block/fdc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/block/fdc.c b/hw/block/fdc.c index 67f78ac702..ed8b367572 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -2700,7 +2700,10 @@ static void isabus_fdc_realize(DeviceState *dev, Error **errp) fdctrl->dma_chann = isa->dma; if (fdctrl->dma_chann != -1) { fdctrl->dma = isa_get_dma(isa_bus_from_device(isadev), isa->dma); - assert(fdctrl->dma); + if (!fdctrl->dma) { + error_setg(errp, "ISA controller does not support DMA, exiting"); + return; + } } qdev_set_legacy_instance_id(dev, isa->iobase, 2); -- 2.11.0