[PATCH v2 2/2] PCI: Fix runtime PM usage count underflow

[Mario Limonciello <superm1@kernel.org>]

From: Mario Limonciello <mario.limonciello@amd.com>

When a USB4 dock is unplugged the PCIe bridge it's connected to will
remove issue a "Link Down" and "Card not detected event". The PCI core
will treat this as a surprise hotplug event and unconfigure all downstream
devices.

When PCI core gets to the point that the device is removed using
pci_device_remove() the runtime count has already been decremented and
so calling pm_runtime_put_sync() will cause an underflow.

Detect the device ishas been disconnected and skip the call for this
cleanup path.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
v2:
 * Use pci_dev_is_disconnected()
v1: https://lore.kernel.org/linux-usb/20250609020223.269407-1-superm1@kernel.org/T/#mf95c947990d016fbfccfd11afe60b8ae08aafa0b
---
 drivers/pci/pci-driver.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 67db34fd10ee7..0d4c67829958b 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -479,7 +479,8 @@ static void pci_device_remove(struct device *dev)
 	pci_iov_remove(pci_dev);
 
 	/* Undo the runtime PM settings in local_pci_probe() */
-	pm_runtime_put_sync(dev);
+	if (!pci_dev_is_disconnected(pci_dev))
+		pm_runtime_put_sync(dev);
 
 	/*
 	 * If the device is still on, set the power state as "unknown",
-- 
2.43.0