3.16.40-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Russell Currey <ruscur@xxxxxxxxxx> commit 04fec21c06e35b169a83e75a84a015ab4606bf5e upstream. eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE. Some callers don't check this, and can cause a null pointer dereference under certain circumstances. Fix this by checking NULL everywhere eeh_pe_bus_get() is called. Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Signed-off-by: Russell Currey <ruscur@xxxxxxxxxx> Reviewed-by: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/powerpc/kernel/eeh_driver.c | 8 ++++++++ arch/powerpc/platforms/powernv/eeh-ioda.c | 5 +++++ 2 files changed, 13 insertions(+) --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -828,6 +828,14 @@ static void eeh_handle_special_event(voi /* Notify all devices to be down */ bus = eeh_pe_bus_get(phb_pe); + if (!bus) { + pr_err("%s: Cannot find PCI bus for " + "PHB#%d-PE#%x\n", + __func__, + pe->phb->global_number, + pe->addr); + break; + } eeh_pe_dev_traverse(pe, eeh_report_failure, NULL); pcibios_remove_pci_devices(bus); --- a/arch/powerpc/platforms/powernv/eeh-ioda.c +++ b/arch/powerpc/platforms/powernv/eeh-ioda.c @@ -578,6 +578,11 @@ static int ioda_eeh_reset(struct eeh_pe ret = ioda_eeh_phb_reset(hose, option); } else { bus = eeh_pe_bus_get(pe); + if (!bus) { + pr_err("%s: Cannot find PCI bus for PHB#%d-PE#%x\n", + __func__, pe->phb->global_number, pe->addr); + return -EIO; + } if (pci_is_root_bus(bus) || pci_is_root_bus(bus->parent)) ret = ioda_eeh_root_reset(hose, option);