From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D942C433F5 for ; Fri, 14 Jan 2022 07:29:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239451AbiANH3b (ORCPT ); Fri, 14 Jan 2022 02:29:31 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:61862 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S239331AbiANH33 (ORCPT ); Fri, 14 Jan 2022 02:29:29 -0500 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 20E7Rhkl026465; Fri, 14 Jan 2022 07:29:08 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : references : date : in-reply-to : message-id : mime-version : content-type; s=pp1; bh=K9IbwkIhXCjF4pxomD0f1QSJ5vymDPmoPBH+CzA8h5A=; b=Ohg1pdrx597dF9Tw2kqdCOoR8h4FpVQGnZTFjxphhnSHvSoAv518s9a8ZainHCXW0DR7 CwC1Pe/adAbVLYjXNmDLXjPwElpiDYdVLJgvBrhhIOi2/4PdDYSOpzVtIQKJyUzVI8s7 B8jNqOtnq1VJJsn7FSnQCMOwtuwRibAGg297iwkCldZpJ8+ZpF4OW69G6rUawUyyFf2O KJNCsYJd0vV+QFrrvKPMGXoEM8bx0col2/mLAX0SZafgCdrWvt7hjqxd9OAdLda/deTp 3KRj2qywmfKXKQ13E4+vBUOjqjlACSDuQ/3d4Y9Rift/+JWto17SO3mOVz8CGdeh8oIM xw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 3dk4t580gu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Jan 2022 07:29:07 +0000 Received: from m0098414.ppops.net (m0098414.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 20E7RVlP025907; Fri, 14 Jan 2022 07:29:07 GMT Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0b-001b2d01.pphosted.com with ESMTP id 3dk4t580gf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Jan 2022 07:29:07 +0000 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 20E7Cm7W017372; Fri, 14 Jan 2022 07:29:05 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma06ams.nl.ibm.com with ESMTP id 3df1vjv9f3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Jan 2022 07:29:05 +0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 20E7T3Xt24969494 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Jan 2022 07:29:03 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0B63F52052; Fri, 14 Jan 2022 07:29:03 +0000 (GMT) Received: from tuxmaker.linux.ibm.com (unknown [9.152.85.9]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTPS id BEEE35204F; Fri, 14 Jan 2022 07:29:02 +0000 (GMT) From: Sven Schnelle To: Steven Rostedt Cc: David Laight , LKML , Ingo Molnar , Andrew Morton , Pingfan Liu , Masami Hiramatsu , Tom Zanussi , hca@linux.ibm.com, deller@gmx.de Subject: Re: [PATCH v2] tracing: Add test for user space strings when filtering on string pointers References: <20220110115532.536088fd@gandalf.local.home> <31c11a47a8bc4e34a1a64d54a54bb944@AcuMS.aculab.com> <20220110122436.5302128f@gandalf.local.home> <7a0fefb7ed3542b4a49dee1e78b1668b@AcuMS.aculab.com> <20220113125754.0cb5273f@gandalf.local.home> <20220113165115.0c844df9@gandalf.local.home> <20220113211501.473ab5ca@gandalf.local.home> Date: Fri, 14 Jan 2022 08:29:02 +0100 In-Reply-To: <20220113211501.473ab5ca@gandalf.local.home> (Steven Rostedt's message of "Thu, 13 Jan 2022 21:15:01 -0500") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-GUID: 4IFYBnwMJsHhvdpNhP1c855tCKiFmjC6 X-Proofpoint-ORIG-GUID: b71Yasxp7VNmCRNXjJ3N5tnrugPx7iIM X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-01-14_02,2022-01-13_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 mlxlogscore=882 impostorscore=0 suspectscore=0 lowpriorityscore=0 phishscore=0 adultscore=0 priorityscore=1501 clxscore=1015 spamscore=0 bulkscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2201140049 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Steven Rostedt writes: > On Thu, 13 Jan 2022 16:51:15 -0500 > Steven Rostedt wrote: > >> We could add something later. As it is currently the merge window, and this >> is a real bug, I'm going to just leave it as is, and we can work to fix the >> other archs later. I need to get a pull request ready by tomorrow. > > Actually I got this working, and looks like a reasonable answer to the > problem. It basically requires that the user specify that the pointer > points into user space for the kernel to read it. > > Thus instead of: > > echo 'filename ~ "trace"' > events/syscalls/sys_enter_openat/filter > > They must now do: > > echo 'filename.ustring ~ "trace"' > events/syscalls/sys_enter_openat/filter > > I updated the documentation to reflect this. Looks good and works on s390, feel free to add my tested-by: Tested-by: Sven Schnelle Thanks!