[PATCH] PCI: stop crashing in pci_release_resource v2

["Christian König" <ckoenig.leichtzumerken@gmail.com>]

Is it entirely possible that the BIOS wasn't able to assign resources to
a device. In this case don't crash in pci_release_resource() when we try
to resize the resource.

v2: keep printing the info that we try to release the BAR

Signed-off-by: Christian König <christian.koenig@amd.com>
CC: stable@vger.kernel.org
---
 drivers/pci/setup-res.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index e815111f3f81..c0f091614805 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -402,6 +402,10 @@ void pci_release_resource(struct pci_dev *dev, int resno)
 	struct resource *res = dev->resource + resno;
 
 	dev_info(&dev->dev, "BAR %d: releasing %pR\n", resno, res);
+
+	if (!res->parent)
+		return;
+
 	release_resource(res);
 	res->end = resource_size(res) - 1;
 	res->start = 0;
-- 
2.14.1