From: Cao jin <caoj.fnst@xxxxxxxxxxxxxx> commit 629823b872402451b42462414da08dddd0e2c93d upstream. When running as guest, under certain condition, it will oops as following. writel() in igb_configure_tx_ring() results in oops, because hw->hw_addr is NULL. While other register access won't oops kernel because they use wr32/rd32 which have a defense against NULL pointer. [ 141.225449] pcieport 0000:00:1c.0: AER: Multiple Uncorrected (Fatal) error received: id=0101 [ 141.225523] igb 0000:01:00.1: PCIe Bus Error: severity=Uncorrected (Fatal), type=Unaccessible, id=0101(Unregistered Agent ID) [ 141.299442] igb 0000:01:00.1: broadcast error_detected message [ 141.300539] igb 0000:01:00.0 enp1s0f0: PCIe link lost, device now detached [ 141.351019] igb 0000:01:00.1 enp1s0f1: PCIe link lost, device now detached [ 143.465904] pcieport 0000:00:1c.0: Root Port link has been reset [ 143.465994] igb 0000:01:00.1: broadcast slot_reset message [ 143.466039] igb 0000:01:00.0: enabling device (0000 -> 0002) [ 144.389078] igb 0000:01:00.1: enabling device (0000 -> 0002) [ 145.312078] igb 0000:01:00.1: broadcast resume message [ 145.322211] BUG: unable to handle kernel paging request at 0000000000003818 [ 145.361275] IP: [<ffffffffa02fd38d>] igb_configure_tx_ring+0x14d/0x280 [igb] [ 145.400048] PGD 0 [ 145.438007] Oops: 0002 [#1] SMP A similar issue & solution could be found at: http://patchwork.ozlabs.org/patch/689592/ Signed-off-by: Cao jin <caoj.fnst@xxxxxxxxxxxxxx> Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/intel/igb/igb_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -3395,7 +3395,7 @@ void igb_configure_tx_ring(struct igb_ad tdba & 0x00000000ffffffffULL); wr32(E1000_TDBAH(reg_idx), tdba >> 32); - ring->tail = hw->hw_addr + E1000_TDT(reg_idx); + ring->tail = adapter->io_addr + E1000_TDT(reg_idx); wr32(E1000_TDH(reg_idx), 0); writel(0, ring->tail); @@ -3734,7 +3734,7 @@ void igb_configure_rx_ring(struct igb_ad ring->count * sizeof(union e1000_adv_rx_desc)); /* initialize head and tail */ - ring->tail = hw->hw_addr + E1000_RDT(reg_idx); + ring->tail = adapter->io_addr + E1000_RDT(reg_idx); wr32(E1000_RDH(reg_idx), 0); writel(0, ring->tail);