This is a note to let you know that I've just added the patch titled
powerpc/eeh: avoid possible crash when edev->pdev changes
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-eeh-avoid-possible-crash-when-edev-pdev-chan.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit bf461f1882f9df63fd779ecf69704eb367c6dbf3
Author: Ganesh Goudar <ganeshgr@xxxxxxxxxxxxx>
Date: Mon Jun 17 19:32:40 2024 +0530
powerpc/eeh: avoid possible crash when edev->pdev changes
[ Upstream commit a1216e62d039bf63a539bbe718536ec789a853dd ]
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->bus.
Signed-off-by: Ganesh Goudar <ganeshgr@xxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://msgid.link/20240617140240.580453-1-ganeshgr@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index e0ce812796241..7d1b50599dd6c 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -849,6 +849,7 @@ struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
{
struct eeh_dev *edev;
struct pci_dev *pdev;
+ struct pci_bus *bus = NULL;
if (pe->type & EEH_PE_PHB)
return pe->phb->bus;
@@ -859,9 +860,11 @@ 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);
if (pdev)
- return pdev->bus;
+ bus = pdev->bus;
+ pci_unlock_rescan_remove();
- return NULL;
+ return bus;
}
