[PATCH 4.4 015/117] PCI: Fix minimum allocation address overwrite

Greg Kroah-Hartman
2016-02-14T22:24:49Z

From: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>

commit 3460baa620685c20f5ee19afb6d99d26150c382c upstream.

Commit 36e097a8a297 ("PCI: Split out bridge window override of minimum
allocation address") claimed to do no functional changes but unfortunately
did: The "min" variable is altered. At least the AVM A1 PCMCIA adapter was
no longer detected, breaking ISDN operation.

Use a local copy of "min" to restore the previous behaviour.

[bhelgaas: avoid gcc "?:" extension for portability and readability]
Fixes: 36e097a8a297 ("PCI: Split out bridge window override of minimum allocation address")
Signed-off-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/pci/bus.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -140,6 +140,8 @@ static int pci_bus_alloc_from_region(str
type_mask |= IORESOURCE_TYPE_BITS;

pci_bus_for_each_resource(bus, r, i) {
+ resource_size_t min_used = min;
+
if (!r)
continue;

@@ -163,12 +165,12 @@ static int pci_bus_alloc_from_region(str
* overrides "min".
*/
if (avail.start)
- min = avail.start;
+ min_used = avail.start;

max = avail.end;

/* Ok, try it out.. */
- ret = allocate_resource(r, res, size, min, max,
+ ret = allocate_resource(r, res, size, min_used, max,
align, alignf, alignf_data);
if (ret == 0)
return 0;