From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id 1CF4E6B07F2 for ; Fri, 17 Aug 2018 07:29:06 -0400 (EDT) Received: by mail-ed1-f72.google.com with SMTP id g15-v6so3046907edm.11 for ; Fri, 17 Aug 2018 04:29:06 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id r52-v6si3755579edd.119.2018.08.17.04.29.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Aug 2018 04:29:04 -0700 (PDT) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w7HBNv9o066976 for ; Fri, 17 Aug 2018 07:29:03 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 2kwte2y4r0-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 17 Aug 2018 07:29:03 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 17 Aug 2018 12:29:01 +0100 Date: Fri, 17 Aug 2018 13:28:50 +0200 From: Heiko Carstens Subject: Re: [PATCH RFC 1/2] drivers/base: export lock_device_hotplug/unlock_device_hotplug References: <20180817075901.4608-1-david@redhat.com> <20180817075901.4608-2-david@redhat.com> <20180817084146.GB14725@kroah.com> <5a5d73e9-e4aa-ffed-a2e3-8aef64e61923@redhat.com> <42df9062-f647-3ad6-5a07-be2b99531119@redhat.com> <20180817100604.GA18164@kroah.com> <4ac624be-d2d6-5975-821f-b20a475781dc@redhat.com> MIME-Version: 1.0 In-Reply-To: <4ac624be-d2d6-5975-821f-b20a475781dc@redhat.com> Message-Id: <20180817112850.GB3565@osiris> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-ID: To: David Hildenbrand Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , Michal Hocko , Benjamin Herrenschmidt , Linux Memory Management List , Paul Mackerras , linux-s390@vger.kernel.org, sthemmin@microsoft.com, Pavel Tatashin , ACPI Devel Maling List , David Rientjes , xen-devel@lists.xenproject.org, Len Brown , haiyangz@microsoft.com, Dan Williams , Andrew Morton , Vlastimil Babka , osalvador@suse.de, "Rafael J. Wysocki" , Linux Kernel Mailing List , Martin Schwidefsky , devel@linuxdriverproject.org, Vitaly Kuznetsov , linuxppc-dev On Fri, Aug 17, 2018 at 01:04:58PM +0200, David Hildenbrand wrote: > >> If there are no objections, I'll go into that direction. But I'll wait > >> for more comments regarding the general concept first. > > > > It is the middle of the merge window, and maintainers are really busy > > right now. I doubt you will get many review comments just yet... > > > > This has been broken since 2015, so I guess it can wait a bit :) I hope you figured out what needs to be locked why. Your patch description seems to be "only" about locking order ;) I tried to figure out and document that partially with 55adc1d05dca ("mm: add private lock to serialize memory hotplug operations"), and that wasn't easy to figure out. I was especially concerned about sprinkling lock/unlock_device_hotplug() calls, which has the potential to make it the next BKL thing.