From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guilherme G. Piccoli Date: Fri, 2 Dec 2016 10:55:56 -0200 Subject: [Intel-wired-lan] [PATCH net v2] igb: re-assign hw address pointer on reset after PCI error In-Reply-To: <1478803603-30306-1-git-send-email-gpiccoli@linux.vnet.ibm.com> References: <1478803603-30306-1-git-send-email-gpiccoli@linux.vnet.ibm.com> Message-ID: <58416F5C.20602@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On 11/10/2016 04:46 PM, Guilherme G. Piccoli wrote: > Whenever the igb driver detects the result of a read operation returns > a value composed only by F's (like 0xFFFFFFFF), it will detach the > net_device, clear the hw_addr pointer and warn to the user that adapter's > link is lost - those steps happen on igb_rd32(). > > In case a PCI error happens on Power architecture, there's a recovery > mechanism called EEH, that will reset the PCI slot and call driver's > handlers to reset the adapter and network functionality as well. > > We observed that once hw_addr is NULL after the error is detected on > igb_rd32(), it's never assigned back, so in the process of resetting > the network functionality we got a NULL pointer dereference in both > igb_configure_tx_ring() and igb_configure_rx_ring(). In order to avoid > such bug, this patch re-assigns the hw_addr value in the slot_reset > handler. > > Reported-by: Anthony H. Thai > Reported-by: Harsha Thyagaraja > Signed-off-by: Guilherme G. Piccoli > --- > drivers/net/ethernet/intel/igb/igb_main.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c > index edc9a6a..136ee9e 100644 > --- a/drivers/net/ethernet/intel/igb/igb_main.c > +++ b/drivers/net/ethernet/intel/igb/igb_main.c > @@ -7878,6 +7878,11 @@ static pci_ers_result_t igb_io_slot_reset(struct pci_dev *pdev) > pci_enable_wake(pdev, PCI_D3hot, 0); > pci_enable_wake(pdev, PCI_D3cold, 0); > > + /* In case of PCI error, adapter lose its HW address > + * so we should re-assign it here. > + */ > + hw->hw_addr = adapter->io_addr; > + > igb_reset(adapter); > wr32(E1000_WUS, ~0); > result = PCI_ERS_RESULT_RECOVERED; > Ping? Sorry to annoy, any news on this? Thanks in advance! Cheers, Guilherme