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spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729890AbeKABn3 (ORCPT ); Wed, 31 Oct 2018 21:43:29 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:60108 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729341AbeKABn3 (ORCPT ); Wed, 31 Oct 2018 21:43:29 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9VGhtJG075712; Wed, 31 Oct 2018 16:44:36 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=qyLJSbiAN97FEQ2UQvo2FZq9eQcid2zxRs+GFHKcaNI=; b=LC43ZfugiC8ZqsB/VF/2ZTHJ/GD0EMFsFLLVEhINi9qj6J+ryeJDB20bIPNp6xDvg9VY NqxzHh4eOQQsWmFsgmgf6D7yx1NOyizJy/LmKOX+3c2YK39YMM15jKbQlzGBY/gjtcvQ dtLxQzJOVNeSVq6uv2FJ18dcZ8YbqehQvES1lYgZZ6N1tcNY/Bi8qO6O4Fl/pxUZ6QVz tb9Ibq3krR7NG5fdxFuokG0NNj6Qq/lIbI54utkjPz+/Z8F8OL7qOOtwi2P7gASEZimJ bnIgyaIGa8O8R4cKBcML7ZUgo8SP2g7HjjnGSCh+OruEdZlfi7S5SmM9YYsomdaHHb+Q Vg== Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by aserp2120.oracle.com with ESMTP id 2ncfyq4a9p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 31 Oct 2018 16:44:36 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w9VGiZ5j015885 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 31 Oct 2018 16:44:35 GMT Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w9VGiYV9005160; Wed, 31 Oct 2018 16:44:34 GMT Received: from [10.209.243.127] (/10.209.243.127) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 31 Oct 2018 09:44:34 -0700 Subject: Re: WARNING in rds_message_alloc_sgs To: Leon Romanovsky Cc: syzbot , linux-rdma@vger.kernel.org, netdev@vger.kernel.org, rds-devel@oss.oracle.com, syzkaller-bugs@googlegroups.com, davem@davemloft.net, linux-kernel@vger.kernel.org References: <0000000000003c6b7b0579772ff3@google.com> <20181031064220.GN3974@mtr-leonro.mtl.com> From: Santosh Shilimkar Organization: Oracle Corporation Message-ID: <1537ebeb-2c03-0068-58f1-6c348a2f718e@oracle.com> Date: Wed, 31 Oct 2018 09:44:28 -0700 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181031064220.GN3974@mtr-leonro.mtl.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9063 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810310139 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/30/2018 11:42 PM, Leon Romanovsky wrote: > On Tue, Oct 30, 2018 at 12:38:02PM -0700, Santosh Shilimkar wrote: >> On 10/30/2018 12:28 PM, syzbot wrote: >>> Hello, >>> >>> syzbot found the following crash on: >>> >>> HEAD commit:    6201f31a39f8 Add linux-next specific files for 20181030 >>> git tree:       linux-next >>> console output: https://syzkaller.appspot.com/x/log.txt?x=1397d06d400000 >>> kernel config:  https://syzkaller.appspot.com/x/.config?x=2a22859d870756c1 >>> dashboard link: >>> https://syzkaller.appspot.com/bug?extid=26de17458aeda9d305d8 >>> compiler:       gcc (GCC) 8.0.1 20180413 (experimental) >>> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10bb52eb400000 >>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=118bdfc5400000 >>> >>> IMPORTANT: if you fix the bug, please add the following tag to the commit: >>> Reported-by: syzbot+26de17458aeda9d305d8@syzkaller.appspotmail.com >>> >>> WARNING: CPU: 0 PID: 19789 at net/rds/message.c:316 >>> rds_message_alloc_sgs+0x10c/0x160 net/rds/message.c:316 >>> Kernel panic - not syncing: panic_on_warn set ... >> Looks like this kernel build has panic on warn enabled which >> triggers panic for " WARN_ON(!nr_pages)" case. Will look into >> it. Thanks !! > > Please don't forget to remove user triggered WARN_ON. > https://lwn.net/Articles/769365/ > "Greg Kroah-Hartman raised the problem of core kernel API code that will > use WARN_ON_ONCE() to complain about bad usage; that will not generate > the desired result if WARN_ON_ONCE() is configured to crash the machine. > He was told that the code should just call pr_warn() instead, and that > the called function should return an error in such situations. It was > generally agreed that any WARN_ON() or WARN_ON_ONCE() calls that can be > triggered from user space need to be fixed." > OK. Thanks for the note !!