[3.13.y.z extended stable] Patch "PCI: mvebu: Fix uninitialized variable in mvebu_get_tgt_attr()" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    PCI: mvebu: Fix uninitialized variable in mvebu_get_tgt_attr()

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 3bc37b71f821e3ed453d761d51c0f19b4e2b4628 Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Date: Wed, 17 Sep 2014 17:58:27 +0200
Subject: PCI: mvebu: Fix uninitialized variable in mvebu_get_tgt_attr()

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 at glider.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
Signed-off-by: Kamal Mostafa <kamal at 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