From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by dpdk.org (Postfix) with ESMTP id 8A0B64C8C; Mon, 5 Nov 2018 15:30:57 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Nov 2018 06:30:49 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,468,1534834800"; d="scan'208";a="84098786" Received: from fyigit-mobl.ger.corp.intel.com (HELO [10.237.221.79]) ([10.237.221.79]) by fmsmga008.fm.intel.com with ESMTP; 05 Nov 2018 06:30:47 -0800 To: "Zhao1, Wei" , "Wu, Jingjing" , "Lu, Wenzhuo" Cc: "dev@dpdk.org" , "stable@dpdk.org" References: <20181028035133.67106-1-ferruh.yigit@intel.com> From: Ferruh Yigit Openpgp: preference=signencrypt Autocrypt: addr=ferruh.yigit@intel.com; prefer-encrypt=mutual; keydata= xsFNBFXZCFABEADCujshBOAaqPZpwShdkzkyGpJ15lmxiSr3jVMqOtQS/sB3FYLT0/d3+bvy qbL9YnlbPyRvZfnP3pXiKwkRoR1RJwEo2BOf6hxdzTmLRtGtwWzI9MwrUPj6n/ldiD58VAGQ +iR1I/z9UBUN/ZMksElA2D7Jgg7vZ78iKwNnd+vLBD6I61kVrZ45Vjo3r+pPOByUBXOUlxp9 GWEKKIrJ4eogqkVNSixN16VYK7xR+5OUkBYUO+sE6etSxCr7BahMPKxH+XPlZZjKrxciaWQb +dElz3Ab4Opl+ZT/bK2huX+W+NJBEBVzjTkhjSTjcyRdxvS1gwWRuXqAml/sh+KQjPV1PPHF YK5LcqLkle+OKTCa82OvUb7cr+ALxATIZXQkgmn+zFT8UzSS3aiBBohg3BtbTIWy51jNlYdy ezUZ4UxKSsFuUTPt+JjHQBvF7WKbmNGS3fCid5Iag4tWOfZoqiCNzxApkVugltxoc6rG2TyX CmI2rP0mQ0GOsGXA3+3c1MCdQFzdIn/5tLBZyKy4F54UFo35eOX8/g7OaE+xrgY/4bZjpxC1 1pd66AAtKb3aNXpHvIfkVV6NYloo52H+FUE5ZDPNCGD0/btFGPWmWRmkPybzColTy7fmPaGz cBcEEqHK4T0aY4UJmE7Ylvg255Kz7s6wGZe6IR3N0cKNv++O7QARAQABzSVGZXJydWggWWln aXQgPGZlcnJ1aC55aWdpdEBpbnRlbC5jb20+wsGVBBMBAgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBNI2U4dCLsKE45mBx/kz60PfE2EfBQJbughWBQkHwjOGAAoJEPkz60Pf E2Eft84QAIbKWqhgqRfoiw/BbXbA1+qm2o4UgkCRQ0yJgt9QsnbpOmPKydHH0ixCliNz1J8e mRXCkMini1bTpnzp7spOjQGLeAFkNFz6BMq8YF2mVWbGEDE9WgnAxZdi0eLY7ZQnHbE6AxKL SXmpe9INb6z3ztseFt7mqje/W/6DWYIMnH3Yz9KzxujFWDcq8UCAvPkxVQXLTMpauhFgYeEx Nub5HbvhxTfUkapLwRQsSd/HbywzqZ3s/bbYMjj5JO3tgMiM9g9HOjv1G2f1dQjHi5YQiTZl 1eIIqQ3pTic6ROaiZqNmQFXPsoOOFfXF8nN2zg8kl/sSdoXWHhama5hbwwtl1vdaygQYlmdK H2ueiFh/UvT3WG3waNv2eZiEbHV8Rk52Xyn2w1G90lV0fYC6Ket1Xjoch7kjwbx793Kz/RfQ rmBY8/S4DTGn3oq3dMdQY+b6+7VMUeLMMh2CXYO9ErkOq+qNTD1IY+cBAkXnaDbQfz0zbste ZGWH74FAZ9nCpDOqbRTrBL42aMGhfOWEyeA1x7+hl6JZfabBWAuf4nnCXuorKHzBXTrf7u7p fXsKQClWRW77PF1VmzrtKNVSytQAmlCWApQIw20AarFipXmVdIjHmJPU611WoyxZPb4JTOxx 5cv9B+nr/RIB+v5dcStyHCCwO1be7nBDdCgd4F6kTQPLzsFNBFfWTL4BEACnNA29e8TarUsB L5n6eLZHXcFvVwNLVlirWOClHXf44o2KnN3ww+eBEmKVfEFo9MSuGDNHS8Zw1NiGMYxLIUgd U6gGrVVs/VrQWL82pbMk6jCj98N+BXIri+6K1z+AImz7ax7iF1kDgRAnFWU0znWWBgM2mM8Y gDjcxfXk4sCKnvf6Gjo08Ey5zmqx7dekAKU2EEp8Q1EJY3jbymLdZWRP4AFFMTS1rGMk0/tt v71NBg1GobCcbNfn9chK/jhqxYhAJqq86RdJQkt3/9x1U1Oq0vXCt4JVVHmkxePtUiuWTTt+ aYlUAsKYZsWvncExvw77x2ArYDmaK0yfjh37wp0lY7DOJHFxoyT8tyWZlLci/VMRG2Ja33xj 0CN4C1yBg+QDeV3QFxQo42iA/ykdXPUR3ezmsND3XKvVLTC4DNb3V/EZQ7jBj64+bEK0VW4G B31VP00ApNQvSoczsIOAKdk97RNbpmPw6q10ILIB+9T1xbnFYzshzGF17oC0/GENIHATx8vZ masOZoDiOZQpeneLgnFE9JfzhLTxv6wNZcc/HLXRQVTkDsQr8ERtkAoHCf1E5+b5Yr7pfnE4 YuhET746o25S53ELUYPIs49qoJsEJL34/oexMfPGyPIlrbufiNyty5jc/1MRwUlhJlJ5IOHy ZUa+6CLR7GdImusFkPJUJwARAQABwsF8BBgBAgAmAhsMFiEE0jZTh0IuwoTjmYHH+TPrQ98T YR8FAlu6CHAFCQXE7zIACgkQ+TPrQ98TYR9nXxAAqNBgkYNyGuWUuy0GwDQCbu3iiMyH1+D7 llafPcK4NYy1Z4AYuVwC9nmLaoj+ozdqS3ncRo57ncRsKEJC46nDJJZYZ5LSJVn63Y3NBF86 lxQAgjj2oyZEwaLKtKbAFsXL43jv1pUGgSvWwYtDwHITXXFQto9rZEuUDRFSx4sg9OR+Q6/6 LY+nQQ3OdHlBkflzYMPcWgDcvcTAO6yasLEUf7UcYoSWTyMYjLB4QuNlXzTswzGVMssJF/vo V8lD1eqqaSUWG3STF6GVLQOr1NLvN5+kUBiEStHFxBpgSCvYY9sNV8FS6N24CAWMBl+10W+D 2h1yiiP5dOdPcBDYKsgqDD91/sP0WdyMJkwdQJtD49f9f+lYloxHnSAxMleOpyscg1pldw+i mPaUY1bmIknLhhkqfMmjywQOXpac5LRMibAAYkcB8v7y3kwELnt8mhqqZy6LUsqcWygNbH/W K3GGt5tRpeIXeJ25x8gg5EBQ0Jnvp/IbBYQfPLtXH0Myq2QuAhk/1q2yEIbVjS+7iowEZNyE 56K63WBJxsJPB2mvmLgn98GqB4G6GufP1ndS0XDti/2K0o8rep9xoY/JDGi0n0L0tk9BHyoP Y7kaEpu7UyY3nVdRLe5H1/MnFG8hdJ97WqnPS0buYZlrbTV0nRFL/NI2VABl18vEEXvNQiO+ vM8= Message-ID: <07fea5ad-c01f-763a-c4b7-0f4948fb421c@intel.com> Date: Mon, 5 Nov 2018 14:30:47 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH] net/avf/base: fix shifting 32 bits signed variable 31 times X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Nov 2018 14:30:58 -0000 On 10/31/2018 3:34 AM, Zhao1, Wei wrote: > > >> -----Original Message----- >> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Ferruh Yigit >> Sent: Sunday, October 28, 2018 11:52 AM >> To: Wu, Jingjing ; Lu, Wenzhuo >> >> Cc: dev@dpdk.org; Yigit, Ferruh ; stable@dpdk.org >> Subject: [dpdk-dev] [PATCH] net/avf/base: fix shifting 32 bits signed variable >> 31 times >> >> Fixes: e5b2a9e957e7 ("net/avf/base: add base code for avf PMD") >> Cc: stable@dpdk.org >> >> Signed-off-by: Ferruh Yigit >> --- >> drivers/net/avf/base/avf_register.h | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/avf/base/avf_register.h >> b/drivers/net/avf/base/avf_register.h >> index ba5a9f3fa..adb989583 100644 >> --- a/drivers/net/avf/base/avf_register.h >> +++ b/drivers/net/avf/base/avf_register.h >> @@ -76,7 +76,7 @@ POSSIBILITY OF SUCH DAMAGE. >> #define AVF_ARQLEN1_ARQCRIT_SHIFT 30 >> #define AVF_ARQLEN1_ARQCRIT_MASK AVF_MASK(0x1, >> AVF_ARQLEN1_ARQCRIT_SHIFT) >> #define AVF_ARQLEN1_ARQENABLE_SHIFT 31 >> -#define AVF_ARQLEN1_ARQENABLE_MASK AVF_MASK(0x1, >> AVF_ARQLEN1_ARQENABLE_SHIFT) >> +#define AVF_ARQLEN1_ARQENABLE_MASK AVF_MASK(0x1U, >> +AVF_ARQLEN1_ARQENABLE_SHIFT) >> #define AVF_ARQT1 0x00007000 /* Reset: EMPR */ >> #define AVF_ARQT1_ARQT_SHIFT 0 >> #define AVF_ARQT1_ARQT_MASK AVF_MASK(0x3FF, >> AVF_ARQT1_ARQT_SHIFT) @@ -99,7 +99,7 @@ POSSIBILITY OF SUCH >> DAMAGE. >> #define AVF_ATQLEN1_ATQCRIT_SHIFT 30 >> #define AVF_ATQLEN1_ATQCRIT_MASK AVF_MASK(0x1, >> AVF_ATQLEN1_ATQCRIT_SHIFT) >> #define AVF_ATQLEN1_ATQENABLE_SHIFT 31 >> -#define AVF_ATQLEN1_ATQENABLE_MASK AVF_MASK(0x1, >> AVF_ATQLEN1_ATQENABLE_SHIFT) >> +#define AVF_ATQLEN1_ATQENABLE_MASK AVF_MASK(0x1U, >> +AVF_ATQLEN1_ATQENABLE_SHIFT) >> #define AVF_ATQT1 0x00008400 /* Reset: EMPR */ >> #define AVF_ATQT1_ATQT_SHIFT 0 >> #define AVF_ATQT1_ATQT_MASK AVF_MASK(0x3FF, >> AVF_ATQT1_ATQT_SHIFT) >> -- >> 2.17.2 > > I have test this code change with a small function to observe the difference. > Reviewed-by: Wei Zhao > > #define AVF_ARQLEN1_ARQENABLE_SHIFT 31 > #define AVF_MASK(mask, shift) (mask << shift) > #define AVF_ARQLEN1_ARQENABLE_MASK1 AVF_MASK(0x1, AVF_ARQLEN1_ARQENABLE_SHIFT) > #define AVF_ARQLEN1_ARQENABLE_MASK2 AVF_MASK(0x1U, AVF_ARQLEN1_ARQENABLE_SHIFT) > > void main(int argc,char **argv) > { > signed int a=1; > > printf("Hello Linux\n"); > printf("%x,=%x\n",AVF_ARQLEN1_ARQENABLE_MASK1,AVF_ARQLEN1_ARQENABLE_MASK2); > printf("a=%x\n",a<<31); > > } I guess you are tying to say there is no difference, output of your code is: Hello Linux 80000000,=80000000 a=80000000 Let's have a little addition to your program, #include #define AVF_ARQLEN1_ARQENABLE_SHIFT 31 #define AVF_MASK(mask, shift) (mask << shift) #define AVF_ARQLEN1_ARQENABLE_MASK1 AVF_MASK(0x1, AVF_ARQLEN1_ARQENABLE_SHIFT) #define AVF_ARQLEN1_ARQENABLE_MASK2 AVF_MASK(0x1U, AVF_ARQLEN1_ARQENABLE_SHIFT) #define AVF_MASK2(mask, shift) (mask >> shift) #define AVF_ARQLEN1_ARQENABLE_MASK11 AVF_MASK2(AVF_ARQLEN1_ARQENABLE_MASK1, 30) #define AVF_ARQLEN1_ARQENABLE_MASK22 AVF_MASK2(AVF_ARQLEN1_ARQENABLE_MASK2, 30) void main(int argc,char **argv) { signed int a=1; printf("Hello Linux\n"); printf("%x,=%x\n", AVF_ARQLEN1_ARQENABLE_MASK1, AVF_ARQLEN1_ARQENABLE_MASK2); printf("%x,=%x\n", AVF_ARQLEN1_ARQENABLE_MASK11, AVF_ARQLEN1_ARQENABLE_MASK22); printf("a=%x\n", a<<31); } Will results same for second line? Both does ((1 << 31) >> 30). '1' is promoted to signed int by default and cppcheck complains that shifting signed variable 31 times is undefined behaviour, and here intention is not really have the 1 as signed integer, so better to fix it. Thanks, ferruh