PCI: plda: Protect root bus removal with rescan lock

Hans Zhang · bjorn-helgaas · commit 4e4f9745f016 · 2026-06-18T11:50:55.000-05:00
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/20260521161822.132996-10-18255117159@163.com
diff --git a/drivers/pci/controller/plda/pcie-plda-host.c b/drivers/pci/controller/plda/pcie-plda-host.c
@@ -640,8 +640,10 @@ EXPORT_SYMBOL_GPL(plda_pcie_host_init);
 
 void plda_pcie_host_deinit(struct plda_pcie_rp *port)
 {
+	pci_lock_rescan_remove();
 	pci_stop_root_bus(port->bridge->bus);
 	pci_remove_root_bus(port->bridge->bus);
+	pci_unlock_rescan_remove();
 
 	plda_pcie_irq_domain_deinit(port);
 

Original file line number	Diff line number	Diff line change
`@@ -640,8 +640,10 @@ EXPORT_SYMBOL_GPL(plda_pcie_host_init);`
`640`	`640`
`641`	`641`	`void plda_pcie_host_deinit(struct plda_pcie_rp *port)`
`642`	`642`	`{`
	`643`	`+ pci_lock_rescan_remove();`
`643`	`644`	`pci_stop_root_bus(port->bridge->bus);`
`644`	`645`	`pci_remove_root_bus(port->bridge->bus);`
	`646`	`+ pci_unlock_rescan_remove();`
`645`	`647`
`646`	`648`	`plda_pcie_irq_domain_deinit(port);`
`647`	`649`