RE: [Intel-wired-lan] [PATCH net v2] igb: re-assign hw address pointer on reset after PCI error
> From: Intel-wired-lan [mailto:intel-wired-lan-boun...@lists.osuosl.org] On > Behalf Of Guilherme G. Piccoli > Sent: Thursday, November 10, 2016 10:47 AM > To: intel-wired-...@lists.osuosl.org > Cc: netdev@vger.kernel.org; gpicc...@linux.vnet.ibm.com > Subject: [Intel-wired-lan] [PATCH net v2] igb: re-assign hw address pointer on > reset after PCI error > > Whenever the igb driver detects the result of a read operation returns > a value composed only by F's (like 0x), 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(+) Tested-by: Aaron Brown
Re: [PATCH net v2] igb: re-assign hw address pointer on reset after PCI error
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 0x), 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 > This seems reasonable. It's similar to what fm10k driver does under this circumstance. Thanks, Jake
Re: [PATCH net v2] igb: re-assign hw address pointer on reset after PCI error
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 0x), 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
[PATCH net v2] igb: re-assign hw address pointer on reset after PCI error
Whenever the igb driver detects the result of a read operation returns a value composed only by F's (like 0x), 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; -- 2.1.0
