On Fri, 2016-12-02 at 10:55 -0200, Guilherme G. Piccoli wrote: > 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 <aht...@us.ibm.com> > > Reported-by: Harsha Thyagaraja <hathy...@in.ibm.com> > > Signed-off-by: Guilherme G. Piccoli <gpicc...@linux.vnet.ibm.com> > > --- > > 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 >
This seems reasonable. It's similar to what fm10k driver does under this circumstance. Thanks, Jake
