Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751332AbdCYK7T (ORCPT ); Sat, 25 Mar 2017 06:59:19 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:60403 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751170AbdCYK7R (ORCPT ); Sat, 25 Mar 2017 06:59:17 -0400 Date: Sat, 25 Mar 2017 11:59:07 +0100 (CET) From: Sebastian Ott X-X-Sender: sebott@schleppi.fritz.box To: Sergey Senozhatsky cc: Petr Mladek , Steven Rostedt , Andrew Morton , Thomas Gleixner , Peter Zijlstra , Linus Torvalds , Michal Hocko , Heiko Carstens , Martin Schwidefsky , linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: Re: lockdep warning: console vs. mem hotplug In-Reply-To: <20170325000442.GD6356@tigerII.localdomain> References: <20170321044421.GB448@jagdpanzerIV.localdomain> <20170325000442.GD6356@tigerII.localdomain> User-Agent: Alpine 2.20 (LFD 67 2015-01-07) Organization: =?ISO-8859-15?Q?=22IBM_Deutschland_Research_&_Development_GmbH_=2F_Vorsitzende_des_Aufsichtsrats=3A_Martina_Koederitz_Gesch=E4ftsf=FChrung=3A_Dirk_Wittkopp_Sitz_der_Gesellschaft=3A_B=F6blingen_=2F_Registergericht?= =?ISO-8859-15?Q?=3A_Amtsgericht_Stuttgart=2C_HRB_243294=22?= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-TM-AS-GCONF: 00 x-cbid: 17032510-0016-0000-0000-000004649214 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17032510-0017-0000-0000-000026F60B0F Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-03-25_09:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1702020001 definitions=main-1703250100 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 794 Lines: 28 On Sat, 25 Mar 2017, Sergey Senozhatsky wrote: > On (03/21/17 13:44), Sergey Senozhatsky wrote: > [..] > > so we probably can > > > > > > 1) move pr_info() out of zone->lock in __offline_isolated_pages(). > > meh... > > > > > > 2) switch to printk_deferred() in __offline_isolated_pages(). > > meh.. there might a bunch of other printks done from under zone->lock. > > > > > > 3) move add_timer() out of sclp_con_lock console in sclp_console_write(). > > well, there can be other consoles that do something similar. > > > > > > 4) ... something smart. > > > Sebastian, does this change make lockdep happy? > > it removes console drivers from the __offline_isolated_pages(). not the > best solution I can think of, but the simplest one. It does. No complaint from lockdep.