increased PCI_MAX_DEVICES constant

[adl09]

This change increases the constant value to ensure proper PCI device enumeration on Supermicro E300-9D hardware.
With the previous value, both 10 GbE NICs (Intel X557-AT2) fail to be detected during initialization, causing PCI passthrough to break.

[midnightveil]

Seems fine.

I'll approve; for other reviewers the reason for there being a hardcoded constant is because there is a hardcoded list of all PCI devices up to this number:

util_libs/libpci/src/pci.c

Line 16 in 486afd6

libpci_device_t libpci_device_list[PCI_MAX_DEVICES];

which is populated by

util_libs/libpci/src/pci.c

Lines 80 to 109 in 486afd6

	static int libpci_add_fun(uint8_t bus, uint8_t dev, uint8_t fun)
	{
	uint16_t vendor_id = libpci_read_reg16(bus, dev, fun, PCI_VENDOR_ID);
	if (vendor_id == PCI_VENDOR_ID_INVALID) {
	/* No device here. */
	return 0;
	}
	ZF_LOGD("PCI :: Device found at BUS %d DEV %d FUN %d:\n", (int)bus, (int)dev, (int)fun);
	ZF_LOGD(" vendorID = %s [0x%x]\n", libpci_vendorID_str(vendor_id), vendor_id);
	uint16_t device_id = libpci_read_reg16(bus, dev, fun, PCI_DEVICE_ID);
	ZF_LOGD(" deviceID = %s [0x%x]\n", libpci_deviceID_str(vendor_id, device_id), device_id);
	if (libpci_num_devices + 1 > PCI_MAX_DEVICES) {
	return 0;
	}
	libpci_device_list[libpci_num_devices].bus = bus;
	libpci_device_list[libpci_num_devices].dev = dev;
	libpci_device_list[libpci_num_devices].fun = fun;
	libpci_device_list[libpci_num_devices].vendor_id = vendor_id;
	libpci_device_list[libpci_num_devices].device_id = device_id;
	libpci_device_list[libpci_num_devices].vendor_name = libpci_vendorID_str(vendor_id);
	libpci_device_list[libpci_num_devices].device_name = libpci_deviceID_str(vendor_id, device_id);
	libpci_device_list[libpci_num_devices].interrupt_line = libpci_read_reg8(bus, dev, fun, PCI_INTERRUPT_LINE);
	libpci_device_list[libpci_num_devices].interrupt_pin = libpci_read_reg8(bus, dev, fun, PCI_INTERRUPT_PIN);
	libpci_device_list[libpci_num_devices].subsystem_id = libpci_read_reg16(bus, dev, fun, PCI_SUBSYSTEM_ID);
	libpci_read_ioconfig(&libpci_device_list[libpci_num_devices].cfg, bus, dev, fun);

.

The other use is

util_libs/libpci/src/virtual_pci.c

Lines 37 to 44 in 486afd6

	libpci_device_t* matched_devices[PCI_MAX_DEVICES];
	int nfound = libpci_find_device_all(vendor_id, device_id, matched_devices);
	for (int i = 0; i < nfound; i++) {
	bool ret = libpci_virtual_pci_device_allow(self, matched_devices[i]);
	if (!ret) return ret;
	}
	return true;
	}

where it allocates a large array on the stack. That is probably the most questionable part of this.