PCI: cadence: Protect root bus removal with rescan lock

Hold the pci_rescan_remove_lock lock while stopping and removing a root bus
to avoid racing with concurrent rescan or hotplug operations triggered via
sysfs.  Such races may lead to use-after-free issues or system crashes.

Signed-off-by: Hans Zhang <18255117159@163.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260521161822.132996-2-18255117159@163.com

diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 0bc9e6e90e0e0075b933cd5fb442bf73a94d48c6..87fd8afa301bf46621f0f4fd8d085ad7af900bff 100644 (file)
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -365,8 +365,10 @@ void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
        struct pci_host_bridge *bridge;
 
        bridge = pci_host_bridge_from_priv(rc);
+       pci_lock_rescan_remove();
        pci_stop_root_bus(bridge->bus);
        pci_remove_root_bus(bridge->bus);
+       pci_unlock_rescan_remove();
 
        cdns_pcie_host_deinit(rc);
        cdns_pcie_host_link_disable(rc);