[PATCH 1/2] PCI/VMD: Detach resources after stopping root bus

[Jon Derrick <jonathan.derrick@intel.com>]

The VMD removal path calls pci_stop_root_bus, which tears down the pcie
tree, including detaching all of the attached drivers. During driver
detachment, devices may use pci_release_region to release resources.
This path relies on the resource being accessible in resource tree.

By detaching the child domain from the parent resource domain prior to
stopping the bus, we are preventing the list traversal from finding the
resource to be freed. If we instead detach the resource after stopping
the bus, we will have properly freed the resource and detaching is
simply accounting at that point.

Without this order, the resource is never freed and is orphaned on VMD
removal, leading to warning:
[  181.940162] Trying to free nonexistent resource <e5a10000-e5a13fff>

Fixes 2c2c5c5cd213aea38c850bb6edc9b7f77f29802f:
"x86/PCI: VMD: Attach VMD resources to parent domain's resource tree"
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
---
 drivers/pci/controller/vmd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index fd2dbd7..46ed80f 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -813,12 +813,12 @@ static void vmd_remove(struct pci_dev *dev)
 {
 	struct vmd_dev *vmd = pci_get_drvdata(dev);
 
-	vmd_detach_resources(vmd);
 	sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
 	pci_stop_root_bus(vmd->bus);
 	pci_remove_root_bus(vmd->bus);
 	vmd_cleanup_srcu(vmd);
 	vmd_teardown_dma_ops(vmd);
+	vmd_detach_resources(vmd);
 	irq_domain_remove(vmd->irq_domain);
 }
 
-- 
1.8.3.1