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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Geert Uytterhoeven , =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Biju Das , Claudiu Beznea , , , References: <20240930160845.8520-1-paul@pbarker.dev> <20240930160845.8520-6-paul@pbarker.dev> <0a779070-d91a-49df-a606-5fc9428e312c@bp.renesas.com> Content-Language: en-US From: Sergey Shtylyov Organization: Open Mobile Platform In-Reply-To: <0a779070-d91a-49df-a606-5fc9428e312c@bp.renesas.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 6.1.0, Database issued on: 10/03/2024 12:53:14 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 19 X-KSE-AntiSpam-Info: Lua profiles 188181 [Oct 03 2024] X-KSE-AntiSpam-Info: Version: 6.1.0.4 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 37 0.3.37 76d1f08bc1e1f80c2a3a76a1cc8929a49fe2f262 X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 213.87.159.233 in (user) b.barracudacentral.org} X-KSE-AntiSpam-Info: {Found in DNSBL: 213.87.159.233 in (user) dbl.spamhaus.org} X-KSE-AntiSpam-Info: d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;omp.ru:7.1.1;127.0.0.199:7.1.2;213.87.159.233:7.1.2 X-KSE-AntiSpam-Info: FromAlignment: s X-KSE-AntiSpam-Info: ApMailHostAddress: 213.87.159.233 X-KSE-AntiSpam-Info: {DNS response errors} X-KSE-AntiSpam-Info: Rate: 19 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=temperror header.from=omp.ru;spf=temperror smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 10/03/2024 12:57:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 10/3/2024 10:36:00 AM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit On 10/3/24 12:23, Paul Barker wrote: [...] >>> From: Paul Barker >>> >>> The HW checksum value is used as a 16-bit flag, it is zero when the >> >> I think I prefer s/HW/hardware/ but there's no hard feelings... :-) >> >>> checksum has been validated and non-zero otherwise. Therefore we don't >>> need to treat this as an actual __wsum type or call csum_unfold(), we >>> can just use a u16 pointer. >>> >>> Signed-off-by: Paul Barker >> [...] >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>> index 1dd2152734b0..9350ca10ab22 100644 >>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >> [...] >>> @@ -762,23 +761,22 @@ static void ravb_rx_csum_gbeth(struct sk_buff *skb) >>> * The last 2 bytes are the protocol checksum status which will be zero >>> * if the checksum has been validated. >>> */ >>> - if (unlikely(skb->len < sizeof(__sum16) * 2)) >>> + csum_len = sizeof(*hw_csum) * 2; >> >> Could've been done by an initializer instead? > > So, if I move this to the initializers at the start of the function, > csum_len must be declared after hw_csum which breaks reverse Christmas > tree ordering: > > struct skb_shared_info *shinfo = skb_shinfo(skb); > u16 *hw_csum; > size_t csum_len = sizeof(*hw_csum) * 2; Could use sizeof(u16) instead, but it's OK to ignore me on this matter. :-) > Thanks, MBR, Sergey