[PATCH] PCI: mvebu: Fix uninitialized variable in mvebu_get_tgt_attr()
From: bhelgaas@google.com (Bjorn Helgaas)
Date: 2014-09-05 17:41:28
Also in:
linux-pci, lkml
Subsystem:
pci subsystem, the rest · Maintainers:
Bjorn Helgaas, Linus Torvalds
On Fri, Aug 08, 2014 at 05:34:05PM +0200, Geert Uytterhoeven wrote:
quoted hunk ↗ jump to hunk
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) { ^ If there's ever gonna be a configuration space or 64-bit memory space entry in DT, rtype will be uninitialized, and the wrong entry may be returned. Initialize rtype to 0 (which is an unused IORESOURCE_* type) to fix this. Introduced in commit 11be65472a427dcf7a11ab6e3e3628f1c6768b5b ("PCI: mvebu: Adapt to the new device tree layout"). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- Alternatively, should the "else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)" just be changed to "else", assuming there can never be other entries than for I/O or 32-bit memory space? --- drivers/pci/host/pci-mvebu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c index ce23e0f076b6..9515f0d13fd4 100644 --- a/drivers/pci/host/pci-mvebu.c +++ b/drivers/pci/host/pci-mvebu.c@@ -877,7 +877,7 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn, u32 flags = of_read_number(range, 1); u32 slot = of_read_number(range + 1, 1); u64 cpuaddr = of_read_number(range + na, pna); - unsigned long rtype; + unsigned long rtype = 0; if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO) rtype = IORESOURCE_IO;-- 1.9.1
This fix looks right to me. I added a stable tag as follows. Thomas
and/or Jason, and you ack this?
commit f96f4040d0d01b6eeacda212cf7db105d06a55ba
Author: Geert Uytterhoeven [off-list ref]
Date: Fri Aug 8 17:34:05 2014 +0200
PCI: mvebu: Fix uninitialized "rtype" in mvebu_get_tgt_attr()
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) {
^
If there's ever a DT entry other than DT_TYPE_IO or DT_TYPE_MEM32,
e.g., a configuration space or 64-bit memory space entry, rtype will
be uninitialized, and the wrong entry may be returned.
Initialize rtype to 0 (which is an unused IORESOURCE_* type) to fix this.
Fixes: 11be65472a42 ("PCI: mvebu: Adapt to the new device tree layout")
Signed-off-by: Geert Uytterhoeven [off-list ref]
Signed-off-by: Bjorn Helgaas [off-list ref]
CC: stable at vger.kernel.org # v3.12+
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index a8c6f1a92e0f..081579c0971e 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c@@ -877,7 +877,7 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn, u32 flags = of_read_number(range, 1); u32 slot = of_read_number(range + 1, 1); u64 cpuaddr = of_read_number(range + na, pna); - unsigned long rtype; + unsigned long rtype = 0; if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO) rtype = IORESOURCE_IO;