[PATCH 2/8] powerpc/pci: Don't scan empty slot
From: Gavin Shan <hidden>
Date: 2014-11-24 22:49:31
Also in:
linux-pci
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
In hotplug case, function pcibios_add_pci_devices() is called to rescan the specified PCI bus, which possibly doesn't have any child devices. Access to the PCI bus's child device node will cause kernel crash without exception. The patch adds two more conditions to avoid the kernel crash. Signed-off-by: Gavin Shan <redacted> --- arch/powerpc/kernel/pci-hotplug.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c
index 6e2b4e3..ea5513b 100644
--- a/arch/powerpc/kernel/pci-hotplug.c
+++ b/arch/powerpc/kernel/pci-hotplug.c@@ -105,7 +105,7 @@ EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices); * is how this routine differs from other, similar pcibios * routines.) */ -void pcibios_add_pci_devices(struct pci_bus * bus) +void pcibios_add_pci_devices(struct pci_bus *bus) { int slotno, mode, pass, max; struct pci_dev *dev;
@@ -120,7 +120,8 @@ void pcibios_add_pci_devices(struct pci_bus * bus) if (mode == PCI_PROBE_DEVTREE) { /* use ofdt-based probe */ of_rescan_bus(dn, bus); - } else if (mode == PCI_PROBE_NORMAL) { + } else if (mode == PCI_PROBE_NORMAL && + dn->child && PCI_DN(dn->child)) { /* * Use legacy probe. In the partial hotplug case, we * probably have grandchildren devices unplugged. So
--
1.8.3.2