From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-x244.google.com (mail-pg0-x244.google.com [IPv6:2607:f8b0:400e:c05::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 418nXz2z1dzDrcd for ; Tue, 19 Jun 2018 09:36:18 +1000 (AEST) Received: by mail-pg0-x244.google.com with SMTP id l65-v6so8251229pgl.8 for ; Mon, 18 Jun 2018 16:36:18 -0700 (PDT) Subject: Re: [PATCH] Revert "net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends" To: Eric Dumazet , Mathieu Malaterre Cc: schwab@linux-m68k.org, "David S. Miller" , Eric Dumazet , LKML , Christophe LEROY , Meelis Roos , netdev@vger.kernel.org, linuxppc-dev References: <20180615185645.8921-1-malat@debian.org> <9d88677a-f2be-2089-79df-15df4e9a5dd6@gmail.com> <87o9g8geu0.fsf@igel.home> <816ef746-5278-1d51-1d9d-55593e377681@gmail.com> <21523399-92ee-f8da-1a3e-0561f62850b7@gmail.com> From: Eric Dumazet Message-ID: Date: Mon, 18 Jun 2018 16:36:15 -0700 MIME-Version: 1.0 In-Reply-To: <21523399-92ee-f8da-1a3e-0561f62850b7@gmail.com> Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 06/18/2018 04:29 PM, Eric Dumazet wrote: > > > On 06/18/2018 11:45 AM, Mathieu Malaterre wrote: > >> >> Here is what I get on my side >> >> [ 53.628847] sungem: sungem wrong csum : 4e04/f97, len 64 bytes >> [ 53.667063] sungem: sungem wrong csum : eea8/6eec, len 149 bytes >> [ 58.648952] sungem: sungem wrong csum : 2095/3d06, len 64 bytes >> [ 58.669414] sungem: sungem wrong csum : 5245/b50, len 149 bytes >> [ 63.674451] sungem: sungem wrong csum : 2d8/5abd, len 149 bytes >> [ 68.678233] sungem: sungem wrong csum : b8fc/a498, len 149 bytes >> [ 73.685771] sungem: sungem wrong csum : 374/5a21, len 149 bytes >> [ 78.689089] sungem: sungem wrong csum : d81/5014, len 149 bytes >> [ 83.683261] sungem: sungem wrong csum : 4e04/f97, len 64 bytes >> [ 83.690193] sungem: sungem wrong csum : c2f7/9a9d, len 149 bytes >> [ 88.692511] sungem: sungem wrong csum : f4d8/68bc, len 149 bytes >> [ 93.699915] sungem: sungem wrong csum : 1370/4a25, len 149 bytes >> [ 98.703136] sungem: sungem wrong csum : e1b5/7bdf, len 149 bytes >> [ 103.704230] sungem: sungem wrong csum : 5321/a74, len 149 bytes >> [ 108.688912] sungem: sungem wrong csum : 2095/3d06, len 64 bytes >> [ 108.706559] sungem: sungem wrong csum : ddbc/7fd8, len 149 bytes >> [ 113.713189] sungem: sungem wrong csum : 5a65/330, len 149 bytes >> [ 113.891697] sungem: sungem wrong csum : 4e04/f97, len 64 bytes >> [ 118.717151] sungem: sungem wrong csum : f7c8/65cc, len 149 bytes >> [ 123.722680] sungem: sungem wrong csum : 3d7a/201b, len 149 bytes >> [ 128.726524] sungem: sungem wrong csum : c8fd/9497, len 149 bytes >> [ 133.732045] sungem: sungem wrong csum : de0d/7f87, len 149 bytes >> [ 135.529163] sungem: sungem wrong csum : 3089/b6dd, len 96 bytes >> [ 135.529208] eth0: hw csum failure >> [ 135.529220] CPU: 0 PID: 0 Comm: swapper Not tainted 4.17.0+ #7 >> [ 135.529226] Call Trace: >> [ 135.529243] [dffedbe0] [c069ddac] >> __skb_checksum_complete+0xf0/0x108 (unreliable) > > Thanks, then I guess next step would be to dump the content of the frames > having a wrong checksum, hoping we find an easy way to discard the CHECKSUM_COMPLETE > in a selective way. > > Otherwise, we will need to remove CHECKSUM_COMPLETE setting in this driver. > > diff --git a/drivers/net/ethernet/sun/sungem.c b/drivers/net/ethernet/sun/sungem.c > index 7a16d40a72d13cf1d522e8a3a396c826fe76f9b9..77a761f95be788bb86c8d917f613c9084818f826 100644 > --- a/drivers/net/ethernet/sun/sungem.c > +++ b/drivers/net/ethernet/sun/sungem.c > @@ -857,6 +857,14 @@ 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 : %04x/%04x, len %u bytes\n", > + csum, csum_fold(rsum), len); > + print_hex_dump(KERN_ERR, "raw data: ", DUMP_PREFIX_OFFSET, DUMP_PREFIX_ADDRESS might give us more information (say alignment problem, or crossing page boundaries) > + 16, 1, skb->data, len, true); > + } > skb->ip_summed = CHECKSUM_COMPLETE; > skb->protocol = eth_type_trans(skb, gp->dev); > >