diff options
| -rw-r--r-- | hw/pci.c | 38 |
1 files changed, 38 insertions, 0 deletions
@@ -1811,6 +1811,25 @@ static uint8_t pci_find_capability_list(PCIDevice *pdev, uint8_t cap_id, return next; } +static uint8_t pci_find_capability_at_offset(PCIDevice *pdev, uint8_t offset) +{ + uint8_t next, prev, found = 0; + + if (!(pdev->used[offset])) { + return 0; + } + + assert(pdev->config[PCI_STATUS] & PCI_STATUS_CAP_LIST); + + for (prev = PCI_CAPABILITY_LIST; (next = pdev->config[prev]); + prev = next + PCI_CAP_LIST_NEXT) { + if (next <= offset && next > found) { + found = next; + } + } + return found; +} + /* Patch the PCI vendor and device ids in a PCI rom image if necessary. This is needed for an option rom which is used for more than one device. */ static void pci_patch_ids(PCIDevice *pdev, uint8_t *ptr, int size) @@ -1952,11 +1971,30 @@ int pci_add_capability(PCIDevice *pdev, uint8_t cap_id, uint8_t offset, uint8_t size) { uint8_t *config; + int i, overlapping_cap; + if (!offset) { offset = pci_find_space(pdev, size); if (!offset) { return -ENOSPC; } + } else { + /* Verify that capabilities don't overlap. Note: device assignment + * depends on this check to verify that the device is not broken. + * Should never trigger for emulated devices, but it's helpful + * for debugging these. */ + for (i = offset; i < offset + size; i++) { + overlapping_cap = pci_find_capability_at_offset(pdev, i); + if (overlapping_cap) { + fprintf(stderr, "ERROR: %04x:%02x:%02x.%x " + "Attempt to add PCI capability %x at offset " + "%x overlaps existing capability %x at offset %x\n", + pci_find_domain(pdev->bus), pci_bus_num(pdev->bus), + PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), + cap_id, offset, overlapping_cap, i); + return -EINVAL; + } + } } config = pdev->config + offset; |