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SubjectRe: [stable] [PATCH 1/3] ath9k: Handle -ENOMEM on RX gracefully
I don't see this patch upstream in Linus's tree.  Am I just missing it
and if so, do you know the git commit id?

thanks,

greg k-h


On Tue, Dec 02, 2008 at 12:51:22PM -0800, Luis R. Rodriguez wrote:
> We would get an oops on RX on -ENOMEM by passing
> NULL to the hardware on ath_rx_buf_link(). The oops
> would look something like this:
>
> ath_rx_tasklet
> ...
> RIP: ath_rx_buf_link
>
> We correct this by handling the allocation for the next
> skb we will put in our RX tail directly on the ath_rx_tasklet()
> *prior* to sending up the last hardware processed
> skb. If we run out of memory this gauranteees we have
> skbs to work with while it simply drops new received
> frames.
>
> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
> ---
> drivers/net/wireless/ath9k/recv.c | 18 ++++++++++++++----
> 1 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/wireless/ath9k/recv.c b/drivers/net/wireless/ath9k/recv.c
> index 0941589..a4f92b2 100644
> --- a/drivers/net/wireless/ath9k/recv.c
> +++ b/drivers/net/wireless/ath9k/recv.c
> @@ -441,18 +441,16 @@ static void ath_rx_requeue(struct ath_softc *sc, struct sk_buff *skb)
> */
> static int ath_rx_indicate(struct ath_softc *sc,
> struct sk_buff *skb,
> + struct sk_buff *nskb,
> struct ath_recv_status *status,
> u16 keyix)
> {
> struct ath_buf *bf = ATH_RX_CONTEXT(skb)->ctx_rxbuf;
> - struct sk_buff *nskb;
> int type;
>
> /* indicate frame to the stack, which will free the old skb. */
> type = ath__rx_indicate(sc, skb, status, keyix);
>
> - /* allocate a new skb and queue it to for H/W processing */
> - nskb = ath_rxbuf_alloc(sc, sc->sc_rxbufsize);
> if (nskb != NULL) {
> bf->bf_mpdu = nskb;
> bf->bf_buf_addr = ath_skb_map_single(sc,
> @@ -741,6 +739,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
> struct ath_desc *ds;
> struct ieee80211_hdr *hdr;
> struct sk_buff *skb = NULL;
> + struct sk_buff *nskb = NULL;
> struct ath_recv_status rx_status;
> struct ath_hal *ah = sc->sc_ah;
> int type, rx_processed = 0;
> @@ -963,6 +962,17 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
> */
> if (sc->sc_rxbufsize < ds->ds_rxstat.rs_datalen)
> goto rx_next;
> +
> + /* allocate a new skb and queue it to for H/W processing */
> + nskb = ath_rxbuf_alloc(sc, sc->sc_rxbufsize);
> +
> + /* Diregard current RX'd frame and reuse the old skb */
> + if (!nskb) {
> + list_move_tail(&bf->list, &sc->sc_rxbuf);
> + ath_rx_buf_link(sc, bf);
> + goto rx_next;
> + }
> +
> /*
> * Sync and unmap the frame. At this point we're
> * committed to passing the sk_buff somewhere so
> @@ -1052,7 +1062,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
>
> /* Pass frames up to the stack. */
>
> - type = ath_rx_indicate(sc, skb,
> + type = ath_rx_indicate(sc, skb, nskb,
> &rx_status, ds->ds_rxstat.rs_keyix);
>
> /*
> --
> 1.5.6.rc2.15.g457bb.dirty
>
> _______________________________________________
> stable mailing list
> stable@linux.kernel.org
> http://linux.kernel.org/mailman/listinfo/stable


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