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| author | Bjorn Helgaas <bhelgaas@google.com> | 2012-06-19 17:45:44 +0400 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2012-06-21 03:28:53 +0400 |
| commit | 8f38eaca55d0fab7499b33adb1dec33e16de5abb (patch) | |
| tree | d5f7a0b123d073b8fb75ca46e82e1862f88a9e13 /drivers/pci | |
| parent | 8291550f8479fde2cee571d1b367e6918819f189 (diff) | |
| download | linux-8f38eaca55d0fab7499b33adb1dec33e16de5abb.tar.xz | |
PCI: fix P2P bridge I/O port window sign extension
On P2P bridges with 32-bit I/O decoding, we incorrectly sign-extended
windows starting at 0x80000000 or above. In "base |= (io_base_hi << 16)",
"io_base_hi" is promoted to a signed int before being extended to an
unsigned long.
This would cause a window starting at I/O address 0x80000000 to be
treated as though it started at 0xffffffff80008000 instead, which
should cause "no compatible bridge window" errors when we enumerate
devices using that I/O space.
The mmio and mmio_pref casts are not strictly necessary, but without
them, correctness depends on the types of the PCI_MEMORY_RANGE_MASK and
PCI_PREF_RANGE_MASK constants, which are not obvious from reading the
local code.
Found by Coverity (CID 138747 and CID 138748).
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/probe.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 658ac977cb56..a7a504fc82b9 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -281,10 +281,11 @@ static void __devinit pci_read_bridge_io(struct pci_bus *child) if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) { u16 io_base_hi, io_limit_hi; + pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi); pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi); - base |= (io_base_hi << 16); - limit |= (io_limit_hi << 16); + base |= ((unsigned long) io_base_hi << 16); + limit |= ((unsigned long) io_limit_hi << 16); } if (base && base <= limit) { @@ -312,8 +313,8 @@ static void __devinit pci_read_bridge_mmio(struct pci_bus *child) res = child->resource[1]; pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo); 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; + base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16; + limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16; if (base && base <= limit) { res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM; region.start = base; @@ -334,11 +335,12 @@ static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child) res = child->resource[2]; pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo); pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo); - base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16; - limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16; + base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16; + limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16; if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) { u32 mem_base_hi, mem_limit_hi; + pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi); pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi); @@ -349,8 +351,8 @@ static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child) */ if (mem_base_hi <= mem_limit_hi) { #if BITS_PER_LONG == 64 - base |= ((long) mem_base_hi) << 32; - limit |= ((long) mem_limit_hi) << 32; + base |= ((unsigned long) mem_base_hi) << 32; + limit |= ((unsigned long) mem_limit_hi) << 32; #else if (mem_base_hi || mem_limit_hi) { dev_err(&dev->dev, "can't handle 64-bit " |