Subject: [PATCH] powerpc/eeh: avoid possible crash when edev->pdev changes

From: Ganesh Goudar <[email-masked]>
Date: Mon, 27 May 2024 13:24:33 +0530

If a PCI device is removed during eeh_pe_report_edev(), edev->pdev
will change and can cause a crash, hold the PCI rescan/remove lock
while taking a copy of edev->pdev.

Signed-off-by: Ganesh Goudar <[email-masked]>
---
 arch/powerpc/kernel/eeh_pe.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index d1030bc52564..49f968733912 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -859,7 +859,9 @@ struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
 
 	/* Retrieve the parent PCI bus of first (top) PCI device */
 	edev = list_first_entry_or_null(&pe->edevs, struct eeh_dev, entry);
+	pci_lock_rescan_remove();
 	pdev = eeh_dev_to_pci_dev(edev);
+	pci_unlock_rescan_remove();
 	if (pdev)
 		return pdev->bus;
 
-- 
2.44.0