From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 5F3D96B0260 for ; Sat, 6 Jan 2018 17:59:33 -0500 (EST) Received: by mail-pg0-f71.google.com with SMTP id z2so4063105pgz.13 for ; Sat, 06 Jan 2018 14:59:33 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [65.50.211.133]) by mx.google.com with ESMTPS id y1si24790pln.324.2018.01.06.14.59.31 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 06 Jan 2018 14:59:32 -0800 (PST) Date: Sat, 6 Jan 2018 14:59:25 -0800 From: Darren Hart Subject: Re: [PATCH] ACPI / WMI: Call acpi_wmi_init() later Message-ID: <20180106225925.GA20169@fury> References: <20171208151159.urdcrzl5qpfd6jnu@earth.li> <2601877.IhOx20xkUK@aspire.rjw.lan> <20180106110227.j2jkxjpjktcy6yjr@earth.li> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180106110227.j2jkxjpjktcy6yjr@earth.li> Sender: owner-linux-mm@kvack.org List-ID: To: Jonathan McDowell Cc: "Rafael J. Wysocki" , Andy Shevchenko , ACPI Devel Maling List , Linux Kernel Mailing List , Linux Memory Management List , Joonsoo Kim , Platform Driver , Andy Lutomirski On Sat, Jan 06, 2018 at 11:02:27AM +0000, Jonathan McDowell wrote: > On Sat, Jan 06, 2018 at 12:30:23AM +0100, Rafael J. Wysocki wrote: > > On Wed, Jan 3, 2018 at 12:49 PM, Rafael J. Wysocki wrote: > > > From: Rafael J. Wysocki > > > > > > Calling acpi_wmi_init() at the subsys_initcall() level causes ordering > > > issues to appear on some systems and they are difficult to reproduce, > > > because there is no guaranteed ordering between subsys_initcall() > > > calls, so they may occur in different orders on different systems. > > > > > > In particular, commit 86d9f48534e8 (mm/slab: fix kmemcg cache > > > creation delayed issue) exposed one of these issues where genl_init() > > > and acpi_wmi_init() are both called at the same initcall level, but > > > the former must run before the latter so as to avoid a NULL pointer > > > dereference. > > > > > > For this reason, move the acpi_wmi_init() invocation to the > > > initcall_sync level which should still be early enough for things > > > to work correctly in the WMI land. > > > > > > Link: https://marc.info/?t=151274596700002&r=1&w=2 > > > Reported-by: Jonathan McDowell > > > Reported-by: Joonsoo Kim > > > Tested-by: Jonathan McDowell > > > Signed-off-by: Rafael J. Wysocki > > > > Guys, this fixes a crash on boot. > > > > If there are no concerns/objections I will just take it through the ACPI tree. > > Note that I first started seeing it in v4.9 so would ideally hit the > appropriate stable trees too. Thanks, I'll take care of that. -- Darren Hart VMware Open Source Technology Center -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org