[PATCH 3.13 027/105] PCI: mvebu: Fix uninitialized variable in mvebu_get_tgt_attr()

Kamal Mostafa
2014-10-27T19:13:30Z

From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

commit 56fab6e189441d714a2bfc8a64f3df9c0749dff7 upstream.

Geert Uytterhoeven reported a warning when building pci-mvebu:

drivers/pci/host/pci-mvebu.c: In function 'mvebu_get_tgt_attr':
drivers/pci/host/pci-mvebu.c:887:39: warning: 'rtype' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (slot == PCI_SLOT(devfn) && type == rtype) {
^

And indeed, the code of mvebu_get_tgt_attr() may lead to the usage of rtype
when being uninitialized, even though it would only happen if we had
entries other than I/O space and 32 bits memory space.

This commit fixes that by simply skipping the current DT range being
considered, if it doesn't match the resource type we're looking for.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/pci/host/pci-mvebu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index d55291c..77044b6 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -824,7 +824,7 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
rangesz = pna + na + ns;
nranges = rlen / sizeof(__be32) / rangesz;

- for (i = 0; i < nranges; i++) {
+ for (i = 0; i < nranges; i++, range += rangesz) {
u32 flags = of_read_number(range, 1);
u32 slot = of_read_number(range + 1, 1);
u64 cpuaddr = of_read_number(range + na, pna);
@@ -834,14 +834,14 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
rtype = IORESOURCE_IO;
else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
rtype = IORESOURCE_MEM;
+ else
+ continue;

if (slot == PCI_SLOT(devfn) && type == rtype) {
*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
return 0;
}
-
- range += rangesz;
}

return -ENOENT;
--
1.9.1