> Date: Fri, 12 Nov 2021 13:22:06 +0100
> From: Stefan Sperling <[email protected]>
>
> The iwx Tx ring array is one entry too short due to an off-by-one error.
>
> Fortunately, this bug is harmless. The last Tx agg queue is never used
> because ieee80211_classify() only returns TID values in the range 0 - 3.
> And iterations over the txq array use nitems() to find the upper bound.
>
> The possiblity of shrinking the txq array by 4 elements to get rid of
> unused Tx agg queues could be investigated later.
> For now, just fix the off-by-one error.
>
> ok?
Can't break anything.
ok kettenis@
> diff b19fd44c79660fc69d55de88265e00892505e7ab
> 0433237ad58131957ccba3ddd837ed772dbec416
> blob - e29148ff81ffa620b806f9244c7ede8f05fb417c
> blob + 4f310ad504e6f81a0ee65a11614dc5bd70f79fef
> --- sys/dev/pci/if_iwxreg.h
> +++ sys/dev/pci/if_iwxreg.h
> @@ -1420,6 +1420,7 @@ struct iwx_gen3_bc_tbl {
> #define IWX_MAX_TID_COUNT 8
> #define IWX_FIRST_AGG_TX_QUEUE (IWX_DQA_MGMT_QUEUE + 1)
> #define IWX_LAST_AGG_TX_QUEUE (IWX_FIRST_AGG_TX_QUEUE +
> IWX_MAX_TID_COUNT - 1)
> +#define IWX_NUM_TX_QUEUES (IWX_LAST_AGG_TX_QUEUE + 1)
>
> /**
> * Max Tx window size is the max number of contiguous TFDs that the scheduler
> blob - 009848fc25471ad90717094d1f67d2f4d22a3d6a
> blob + 719d9b6295b9eb9c31b36a98bcb0259a8a2f4cf3
> --- sys/dev/pci/if_iwxvar.h
> +++ sys/dev/pci/if_iwxvar.h
> @@ -497,7 +497,7 @@ struct iwx_softc {
> int sc_msix;
>
> /* TX/RX rings. */
> - struct iwx_tx_ring txq[IWX_LAST_AGG_TX_QUEUE];
> + struct iwx_tx_ring txq[IWX_NUM_TX_QUEUES];
> struct iwx_rx_ring rxq;
> int qfullmsk;
> int qenablemsk;
>
>
