Re: [PATCH] Revert "net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends"
From: Andreas Schwab
Date: Tue Jun 19 2018 - 18:32:26 EST
On Jun 19 2018, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> diff --git a/drivers/net/ethernet/sun/sungem.c b/drivers/net/ethernet/sun/sungem.c
> index 7a16d40a72d13cf1d522e8a3a396c826fe76f9b9..672d6748ab44f0890e92d5ca55d6ff6834c20dc9 100644
> --- a/drivers/net/ethernet/sun/sungem.c
> +++ b/drivers/net/ethernet/sun/sungem.c
> @@ -60,8 +60,7 @@
> #include <linux/sungem_phy.h>
> #include "sungem.h"
>
> -/* Stripping FCS is causing problems, disabled for now */
> -#undef STRIP_FCS
> +#define STRIP_FCS
>
> #define DEFAULT_MSG (NETIF_MSG_DRV | \
> NETIF_MSG_PROBE | \
> @@ -435,7 +434,7 @@ static int gem_rxmac_reset(struct gem *gp)
> writel(desc_dma & 0xffffffff, gp->regs + RXDMA_DBLOW);
> writel(RX_RING_SIZE - 4, gp->regs + RXDMA_KICK);
> val = (RXDMA_CFG_BASE | (RX_OFFSET << 10) |
> - ((14 / 2) << 13) | RXDMA_CFG_FTHRESH_128);
> + (ETH_HLEN << 13) | RXDMA_CFG_FTHRESH_128);
> writel(val, gp->regs + RXDMA_CFG);
> if (readl(gp->regs + GREG_BIFCFG) & GREG_BIFCFG_M66EN)
> writel(((5 & RXDMA_BLANK_IPKTS) |
> @@ -857,6 +856,14 @@ static int gem_rx(struct gem *gp, int work_to_do)
>
> csum = (__force __sum16)htons((status & RXDCTRL_TCPCSUM) ^ 0xffff);
> skb->csum = csum_unfold(csum);
> + {
> + __wsum rsum = csum_partial(skb->data + ETH_HLEN, len - ETH_HLEN, 0);
> + if (csum != csum_fold(rsum) && net_ratelimit())
> + pr_err("sungem wrong csum : %x/%x, len %u bytes\n",
> + csum, csum_fold(rsum), len);
> + print_hex_dump(KERN_ERR, "raw data: ", DUMP_PREFIX_OFFSET,
> + 16, 1, skb->data, len, true);
> + }
> skb->ip_summed = CHECKSUM_COMPLETE;
> skb->protocol = eth_type_trans(skb, gp->dev);
>
> @@ -1761,7 +1768,7 @@ static void gem_init_dma(struct gem *gp)
> writel(0, gp->regs + TXDMA_KICK);
>
> val = (RXDMA_CFG_BASE | (RX_OFFSET << 10) |
> - ((14 / 2) << 13) | RXDMA_CFG_FTHRESH_128);
> + (ETH_HLEN << 13) | RXDMA_CFG_FTHRESH_128);
> writel(val, gp->regs + RXDMA_CFG);
>
> writel(desc_dma >> 32, gp->regs + RXDMA_DBHI);
With that patch I still get the wrong csum messages, but no longer the
hw csum failure messages (tested on a PowerMac G5).
[ 662.659767] sungem: sungem wrong csum : 8359/7ca6, len 86 bytes, c0000001fee9cc02
[ 662.659775] raw data: 00000000: 00 0d 93 43 81 62 d4 3d 7e 4c 48 b7 86 dd 61 01 ...C.b.=~LH...a.
[ 662.659778] raw data: 00000010: 1c 1e 00 20 06 40 20 01 0a 62 17 11 88 01 00 00 ... .@ ..b......
[ 662.659780] raw data: 00000020: 00 00 00 00 0a 38 20 01 0a 62 17 11 88 01 00 00 .....8 ..b......
[ 662.659783] raw data: 00000030: 00 00 00 00 00 07 9a 18 00 16 c1 9a 7e ea ea 44 ............~..D
[ 662.659785] raw data: 00000040: fb 4a 80 10 05 93 44 08 00 00 01 01 08 0a 59 68 .J....D.......Yh
[ 662.659788] raw data: 00000050: ba e2 0e bb ac ae ......
Andreas.
--
Andreas Schwab, schwab@xxxxxxxxxxxxxx
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
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