[SeaBIOS] [PATCH] pci: panic when out of bus numbers

[Marcel Apfelbaum]

Currently the bios goes into an endless loop if more than
255 PCI buses are requested.

Change that to panic which is preferred in this case.

Signed-off-by: Marcel Apfelbaum 
---

Hi,

I am well aware that this is not a common scenario, but the bug was found
and maybe it deserves a little attention.

I opted for using panic because I saw it used for other scenarios
where the bios is out of resources.

Another way to look at this would be to *stop* registering buses
over 255 and loose some of the devices, but bring the system up.

Thanks,
Marcel

src/fw/pciinit.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c
index c31c2fa..5da6cf6 100644
--- a/src/fw/pciinit.c
+++ b/src/fw/pciinit.c
@@ -469,6 +469,9 @@ pci_bios_init_bus_rec(int bus, u8 *pci_bus)

u8 secbus = pci_config_readb(bdf, PCI_SECONDARY_BUS);
         (*pci_bus)++;
+        if (!(*pci_bus)) {
+            panic("PCI: out of bus numbers!\n");
+        }
         if (*pci_bus != secbus) {
             dprintf(1, "PCI: secondary bus = 0x%x -> 0x%x\n",
                     secbus, *pci_bus);