On Mon, Jul 14, 2014 at 11:48 PM, Nikolai Zhubr <n-a-zh...@yandex.ru> wrote: > 14.07.2014 20:44, Jonas Gorski: > [...] > >>> If I were to speculate wildly, I would guess that B44_RXMAXLEN refers to >>> the maximum frame length, not the maximum buffer length - and in the >>> code, it's being fed with the maximum buffer length. >>> This would allow the hardware to receive slightly oversized frames which >>> can corrupt the skb. >> >> >> Since there is a public datasheet[1], this is easily verifiable, and >> it looks you are right: >> >> "Receive Maximum Length Register (RcvLength, Offset 0x404): >> >> The value stored in this register specifies the largest valid Ethernet >> Frame to be received." > > > Ok, so I'd suppose > bw32(bp, B44_RXMAXLEN, bp->dev->mtu + ETH_HLEN + 8 + RX_HEADER_LEN) > should instead be > bw32(bp, B44_RXMAXLEN, bp->dev->mtu + ETH_HLEN) ? > or > bw32(bp, B44_RXMAXLEN, bp->dev->mtu + ETH_HLEN + 8) ?
This is the right one; mtu (the "payload") + ETH_HLEN (14 bytes) + 8 (4 bytes for vlan tag, probably 4 extra bytes for custom header optionally used by broadcom switches) > or maybe even > bw32(bp, B44_RXMAXLEN, bp->dev->mtu) ? > > Apology for my ignorance, just can't stand testing it immediately to > hopefully get it right for BB. > > > Thank you. > Nikolai Thanks for testing! Jonas _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel
