fdc: Exit if ISA controller does not support DMA

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 <aik@ozlabs.ru>
[thuth: Slightly adjusted error message and updated scripts/device-crash-test]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1521193892-15552-3-git-send-email-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index 7b7dd41296d006657e5429d9a0b0b8ab495d86dd..cd29e27d8f594338463d4b858eeda12253e32b17 100644 (file)
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -2695,7 +2695,10 @@ 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");
+            return;
+        }
     }
 
     qdev_set_legacy_instance_id(dev, isa->iobase, 2);