static void test_bmdma_no_busmaster(void) { QPCIDevice *dev; void *bmdma_base, *ide_base; uint8_t status; dev = get_pci_device(&bmdma_base, &ide_base); /* No PRDT_EOT, each entry addr 0/size 64k, and in theory qemu shouldn't be * able to access it anyway because the Bus Master bit in the PCI command * register isn't set. This is complete nonsense, but it used to be pretty * good at confusing and occasionally crashing qemu. */ PrdtEntry prdt[4096] = { }; status = send_dma_request(CMD_READ_DMA | CMDF_NO_BM, 0, 512, prdt, ARRAY_SIZE(prdt), NULL); /* Not entirely clear what the expected result is, but this is what we get * in practice. At least we want to be aware of any changes. */ g_assert_cmphex(status, ==, BM_STS_ACTIVE | BM_STS_INTR); assert_bit_clear(qpci_io_readb(dev, ide_base + reg_status), DF | ERR); }