From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f196.google.com (mail-wr0-f196.google.com [209.85.128.196]) by dpdk.org (Postfix) with ESMTP id DE6BA2C6A for ; Wed, 23 May 2018 16:34:16 +0200 (CEST) Received: by mail-wr0-f196.google.com with SMTP id l41-v6so1706348wre.7 for ; Wed, 23 May 2018 07:34:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=etAIdd0OI1GfedFQ/pX84KfMdHC8tr/97aKxuIaRaGY=; b=mj/bjKcEPJSsuj6wJx/tHt6Rm4zX21f0M3IbX7iKDj3hZ7riwTd06fCpIArfI9ZU8W eMlxmz1WtBkhvAOASmyOdEVkb/GjH9tkUFe9dOv+E0ewOgMlR34+vh9WHPSFqrx28foA ifPm2Zw5XH/Jp1u0hrFKImBLptJ0SXedm63Gu2X6BQZuOYKetuoDnyOS2E/g90jlvMdw OFxN2qEoW9wvz42+bQX5sTaf0MsSgcPNjhciBgdByXaZLYXyXngUgbdBBIwlEcogUjBd Ouq40nmSoCZhwkd/e69DMKLCRm1NiVwg8L8N0KVMALWcUGVsCQyUYds0C/u0ucrL3xF0 PgAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=etAIdd0OI1GfedFQ/pX84KfMdHC8tr/97aKxuIaRaGY=; b=mwoSfSbgd32t7TWCxa0fKQbk1I2nZjutmi2NrJB8AjK6CRPqwQr83uWAX43YqFYuw5 1mFdyHfsyR3XBdEzwfkFUtOHxlJYSJWuBAAoTcywP2aCjAxWjovb86w3hh111/x9cs8G mygfJhsXNNmWVhk/ZEIq2fSiqYTypn7W1r8yTbj6owt0Hpk5mEd28dtkxBy9kTqffXV4 0TPlbMbOl9JGk15mjd+286Hs+jhdTg5Ucm79fRbvSggnBf9fecQgECTDKMiEVDAvKtGz 3WCsOjo6Jo3aWjk+KCKgyOdZFc2z/e/UlVlzw9V6WEFIyZ4GesjoUOfgucosczT+0qZS HCEw== X-Gm-Message-State: ALKqPwdj5Q7Mh3B0pCHVzn0zGLow1cMvPrYuNYZliX6v3rli0ldDmRdZ D6xPuCynjoeOewbhgcHZbos= X-Google-Smtp-Source: AB8JxZrNzGDFQRGWR11ATx6iuwxxsCdlePEfJ5T194FwtzgGyxgAwTMG+Exzi2IV5mpSgI70r6b12Q== X-Received: by 2002:adf:c358:: with SMTP id e24-v6mr2625223wrg.86.1527086056636; Wed, 23 May 2018 07:34:16 -0700 (PDT) Received: from localhost ([2a00:23c5:be9a:5200:ce4c:82c0:d567:ecbb]) by smtp.gmail.com with ESMTPSA id 38-v6sm44622161wry.61.2018.05.23.07.34.15 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 23 May 2018 07:34:15 -0700 (PDT) From: luca.boccassi@gmail.com To: Andy Green Cc: Bruce Richardson , dpdk stable Date: Wed, 23 May 2018 15:33:37 +0100 Message-Id: <20180523143344.16885-16-luca.boccassi@gmail.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180523143344.16885-1-luca.boccassi@gmail.com> References: <20180516100945.4449-2-luca.boccassi@gmail.com> <20180523143344.16885-1-luca.boccassi@gmail.com> Subject: [dpdk-stable] patch 'mbuf: avoid integer promotion in prepend/adj/chain' has been queued to LTS release 16.11.7 X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 May 2018 14:34:17 -0000 Hi, FYI, your patch has been queued to LTS release 16.11.7 Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet. It will be pushed if I get no objections before 05/25/18. So please shout if anyone has objections. Thanks. Luca Boccassi --- >>From d0094bc1093e327fef511801cc45b0b1f7bbc974 Mon Sep 17 00:00:00 2001 From: Andy Green Date: Tue, 22 May 2018 09:24:42 +0800 Subject: [PATCH] mbuf: avoid integer promotion in prepend/adj/chain [ upstream commit 9d0b59f84e1170b12a128cdcccab5711f25b5dd8 ] GCC 8.1 warned: In function 'rte_pktmbuf_prepend': rte_mbuf.h:1908:17: warning: conversion from 'int' to 'uint16_t' {aka 'short unsigned int'} may change value [-Wconversion] m->data_off -= len; ^~~ m->data_off is a uint16_t uint16_t data_off; len (a uint16_t) is promoted to an int using -=. Do the subtraction explicitly and cast the result to uint16_t. The below += or -= changes are solving the same thing. In function 'rte_pktmbuf_adj': rte_mbuf.h:1969:17: warning: conversion from 'int' to 'uint16_t' {aka 'short unsigned int'} may change value [-Wconversion] m->data_off += len; ^~~ In function 'rte_pktmbuf_chain': rte_mbuf.h:2082:19: warning: conversion from 'int' to 'uint16_t' {aka 'short unsigned int'} may change value [-Wconversion] head->nb_segs += tail->nb_segs; ^~~~ Also uint16_t uint16_t nb_segs; /**< Number of segments. */ Fixes: 08b563ffb19d ("mbuf: replace data pointer by an offset") Fixes: 1a60a0daa6e4 ("mbuf: fix segments number type increase") Signed-off-by: Andy Green Acked-by: Bruce Richardson --- lib/librte_mbuf/rte_mbuf.h | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h index 25ef1a37f..5b7546456 100644 --- a/lib/librte_mbuf/rte_mbuf.h +++ b/lib/librte_mbuf/rte_mbuf.h @@ -1456,7 +1456,10 @@ static inline char *rte_pktmbuf_prepend(struct rte_mbuf *m, if (unlikely(len > rte_pktmbuf_headroom(m))) return NULL; - m->data_off -= len; + /* NB: elaborating the subtraction like this instead of using + * -= allows us to ensure the result type is uint16_t + * avoiding compiler warnings on gcc 8.1 at least */ + m->data_off = (uint16_t)(m->data_off - len); m->data_len = (uint16_t)(m->data_len + len); m->pkt_len = (m->pkt_len + len); @@ -1516,8 +1519,11 @@ static inline char *rte_pktmbuf_adj(struct rte_mbuf *m, uint16_t len) if (unlikely(len > m->data_len)) return NULL; + /* NB: elaborating the addition like this instead of using + * += allows us to ensure the result type is uint16_t + * avoiding compiler warnings on gcc 8.1 at least */ m->data_len = (uint16_t)(m->data_len - len); - m->data_off += len; + m->data_off = (uint16_t)(m->data_off + len); m->pkt_len = (m->pkt_len - len); return (char *)m->buf_addr + m->data_off; } @@ -1629,7 +1635,10 @@ static inline int rte_pktmbuf_chain(struct rte_mbuf *head, struct rte_mbuf *tail cur_tail = rte_pktmbuf_lastseg(head); cur_tail->next = tail; - /* accumulate number of segments and total length. */ + /* accumulate number of segments and total length. + * NB: elaborating the addition like this instead of using + * -= allows us to ensure the result type is uint16_t + * avoiding compiler warnings on gcc 8.1 at least */ head->nb_segs = (uint8_t)(head->nb_segs + tail->nb_segs); head->pkt_len += tail->pkt_len; -- 2.14.2