PCI: reject mmio ranges starting at 0 on pci_bridge read

We already track unassigned resources in struct resource, and this
prevents us from overwriting resource flags and info in the unassigned
case.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 233d1c275d96aa885df906bcd0a30fd019ff601a..d3009430eab69cb47a190991fae884ef9180405b 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -316,13 +316,17 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
                limit |= (io_limit_hi << 16);
        }
 
-       if (base <= limit) {
+       if (base && base <= limit) {
                res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
                if (!res->start)
                        res->start = base;
                if (!res->end)
                        res->end = limit + 0xfff;
                dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+       } else {
+               dev_printk(KERN_DEBUG, &dev->dev,
+                        "  bridge window [io  %04lx - %04lx] reg reading\n",
+                                base, limit);
        }
 
        res = child->resource[1];
@@ -330,11 +334,15 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
        pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
        base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
        limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
-       if (base <= limit) {
+       if (base && base <= limit) {
                res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
                res->start = base;
                res->end = limit + 0xfffff;
                dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+       } else {
+               dev_printk(KERN_DEBUG, &dev->dev,
+                       "  bridge window [mem 0x%08lx - 0x%08lx] reg reading\n",
+                                        base, limit + 0xfffff);
        }
 
        res = child->resource[2];
@@ -366,7 +374,7 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 #endif
                }
        }
-       if (base <= limit) {
+       if (base && base <= limit) {
                res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
                                         IORESOURCE_MEM | IORESOURCE_PREFETCH;
                if (res->flags & PCI_PREF_RANGE_TYPE_64)
@@ -374,6 +382,10 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
                res->start = base;
                res->end = limit + 0xfffff;
                dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+       } else {
+               dev_printk(KERN_DEBUG, &dev->dev,
+                    "  bridge window [mem 0x%08lx - %08lx pref] reg reading\n",
+                                        base, limit + 0xfffff);
        }
 }