diff options
| -rw-r--r-- | drivers/pcmcia/rsrc_nonstatic.c | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/drivers/pcmcia/rsrc_nonstatic.c b/drivers/pcmcia/rsrc_nonstatic.c index ba5256debde2..dcd1a4ad3d63 100644 --- a/drivers/pcmcia/rsrc_nonstatic.c +++ b/drivers/pcmcia/rsrc_nonstatic.c @@ -935,23 +935,42 @@ static int nonstatic_autoadd_resources(struct pcmcia_socket *s) return -ENODEV; #if defined(CONFIG_X86) - /* If this is the root bus, the risk of hitting - * some strange system devices which aren't protected - * by either ACPI resource tables or properly requested - * resources is too big. Therefore, don't do auto-adding - * of resources at the moment. + /* If this is the root bus, the risk of hitting some strange + * system devices is too high: If a driver isn't loaded, the + * resources are not claimed; even if a driver is loaded, it + * may not request all resources or even the wrong one. We + * can neither trust the rest of the kernel nor ACPI/PNP and + * CRS parsing to get it right. Therefore, use several + * safeguards: + * + * - Do not auto-add resources if the CardBus bridge is on + * the PCI root bus + * + * - Avoid any I/O ports < 0x100. + * + * - On PCI-PCI bridges, only use resources which are set up + * exclusively for the secondary PCI bus: the risk of hitting + * system devices is quite low, as they usually aren't + * connected to the secondary PCI bus. */ if (s->cb_dev->bus->number == 0) return -EINVAL; -#endif + for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) { + res = s->cb_dev->bus->resource[i]; +#else pci_bus_for_each_resource(s->cb_dev->bus, res, i) { +#endif if (!res) continue; if (res->flags & IORESOURCE_IO) { + /* safeguard against the root resource, where the + * risk of hitting any other device would be too + * high */ if (res == &ioport_resource) continue; + dev_printk(KERN_INFO, &s->cb_dev->dev, "pcmcia: parent PCI bridge window: %pR\n", res); @@ -961,8 +980,12 @@ static int nonstatic_autoadd_resources(struct pcmcia_socket *s) } if (res->flags & IORESOURCE_MEM) { + /* safeguard against the root resource, where the + * risk of hitting any other device would be too + * high */ if (res == &iomem_resource) continue; + dev_printk(KERN_INFO, &s->cb_dev->dev, "pcmcia: parent PCI bridge window: %pR\n", res); |