Re: [PATCH] igb: use igb_adapter->io_addr instead of e1000_hw->hw_addr

From: Alexander Duyck
Date: Wed Nov 09 2016 - 11:28:40 EST


On Mon, Nov 7, 2016 at 11:06 PM, Cao jin <caoj.fnst@xxxxxxxxxxxxxx> wrote:
> 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 similiar issue & solution could be found at:
> http://patchwork.ozlabs.org/patch/689592/
>
> Signed-off-by: Cao jin <caoj.fnst@xxxxxxxxxxxxxx>
> ---
> drivers/net/ethernet/intel/igb/igb_main.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
> index edc9a6a..3f240ac 100644
> --- a/drivers/net/ethernet/intel/igb/igb_main.c
> +++ b/drivers/net/ethernet/intel/igb/igb_main.c
> @@ -3390,7 +3390,7 @@ void igb_configure_tx_ring(struct igb_adapter *adapter,
> 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);
>
> @@ -3729,7 +3729,7 @@ void igb_configure_rx_ring(struct igb_adapter *adapter,
> 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);
>

This patch looks good to me.

Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>