Merge tag 'pci-v6.8-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci fixes from Bjorn Helgaas:

 - Keep bridges in D0 if we need to poll downstream devices for PME to
   resolve a v6.6 regression where we failed to enumerate devices below
   bridges put in D3hot by runtime PM, e.g., NVMe drives connected via
   Thunderbolt or USB4 docks (Alex Williamson)

 - Add Siddharth Vadapalli as PCI TI DRA7XX/J721E reviewer

* tag 'pci-v6.8-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  MAINTAINERS: Add Siddharth Vadapalli as PCI TI DRA7XX/J721E reviewer
  PCI: Fix active state requirement in PME polling

1 files changed, 22 insertions, 15 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 9ab9b1008d8b..c3585229c12a 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2522,29 +2522,36 @@ static void pci_pme_list_scan(struct work_struct *work)
 		if (pdev->pme_poll) {
 			struct pci_dev *bridge = pdev->bus->self;
 			struct device *dev = &pdev->dev;
-			int pm_status;
+			struct device *bdev = bridge ? &bridge->dev : NULL;
+			int bref = 0;
 
 			/*
-			 * If bridge is in low power state, the
-			 * configuration space of subordinate devices
-			 * may be not accessible
+			 * If we have a bridge, it should be in an active/D0
+			 * state or the configuration space of subordinate
+			 * devices may not be accessible or stable over the
+			 * course of the call.
 			 */
-			if (bridge && bridge->current_state != PCI_D0)
-				continue;
+			if (bdev) {
+				bref = pm_runtime_get_if_active(bdev, true);
+				if (!bref)
+					continue;
+
+				if (bridge->current_state != PCI_D0)
+					goto put_bridge;
+			}
 
 			/*
-			 * If the device is in a low power state it
-			 * should not be polled either.
+			 * The device itself should be suspended but config
+			 * space must be accessible, therefore it cannot be in
+			 * D3cold.
 			 */
-			pm_status = pm_runtime_get_if_active(dev, true);
-			if (!pm_status)
-				continue;
-
-			if (pdev->current_state != PCI_D3cold)
+			if (pm_runtime_suspended(dev) &&
+			    pdev->current_state != PCI_D3cold)
 				pci_pme_wakeup(pdev, NULL);
 
-			if (pm_status > 0)
-				pm_runtime_put(dev);
+put_bridge:
+			if (bref > 0)
+				pm_runtime_put(bdev);
 		} else {
 			list_del(&pme_dev->list);
 			kfree(pme_dev);