From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756310AbcINCi2 (ORCPT ); Tue, 13 Sep 2016 22:38:28 -0400 Received: from mail-it0-f66.google.com ([209.85.214.66]:35859 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755514AbcINCiY (ORCPT ); Tue, 13 Sep 2016 22:38:24 -0400 Subject: Re: [RFC] fs: add userspace critical mounts event support To: "Luis R. Rodriguez" , Daniel Vetter , Mimi Zohar , Felix Fietkau , David Woodhouse , Roman Pen , Bjorn Andersson , Ming Lei , Andrew Morton , Michal Marek , Greg KH References: <1466117661-22075-1-git-send-email-mcgrof@kernel.org> <1466117661-22075-3-git-send-email-mcgrof@kernel.org> <20160824203901.GT3296@wotan.suse.de> <20160825194133.GC3296@wotan.suse.de> <20160902235916.GO3296@wotan.suse.de> <20160903002014.GP3296@wotan.suse.de> Cc: Linux Kernel Mailing List , Vikram Mulukutla , Stephen Boyd , Mark Brown , Takashi Iwai , Johannes Berg , Christian Lamparter , hauke@hauke-m.de, Josh Boyer , Dmitry Torokhov , jslaby@suse.com, Linus Torvalds , Andy Lutomirski , Wu Fengguang , rpurdie@rpsys.net, Jeff Mahoney , j.anaszewski@samsung.com, Abhay_Salunke@dell.com, Julia Lawall , Gilles.Muller@lip6.fr, nicolas.palix@imag.fr, Tom Gundersen , Kay Sievers , David Howells , Alessandro Rubini , Kevin Cernekee , Kees Cook , Jonathan Corbet , Thierry Martinez , cocci@systeme.lip6.fr, linux-serial@vger.kernel.org, linux-doc@vger.kernel.org, linuxppc-dev From: Rob Landley Message-ID: <6332a54e-74c6-eafd-368e-71e87a3fa34e@landley.net> Date: Tue, 13 Sep 2016 21:38:17 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20160903002014.GP3296@wotan.suse.de> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/02/2016 07:20 PM, Luis R. Rodriguez wrote: > kernel_read_file_from_path() can try to read a file from > the system's filesystem. This is typically done for firmware > for instance, which lives in /lib/firmware. One issue with > this is that the kernel cannot know for sure when the real > final /lib/firmare/ is ready, and even if you use initramfs > drivers are currently initialized *first* prior to the initramfs > kicking off. Why? > During init we run through all init calls first > (do_initcalls()) and finally the initramfs is processed via > prepare_namespace(): What's the downside of moving initramfs cpio extraction earlier in the boot? I did some shuffling around of those code to make initmpfs work, does anybody know why initramfs extraction _before_ we initialize drivers would be a bad thing? (The cpio is in memory, either linked into the kernel or from the bootloader. No drivers are needed to extract it, that's sort of the point.) The only things I can think of are memory churn (large contiguous physical page allocations), or if a driver somehow got us access to more physical memory? Rob From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Landley Subject: Re: [RFC] fs: add userspace critical mounts event support Date: Tue, 13 Sep 2016 21:38:17 -0500 Message-ID: <6332a54e-74c6-eafd-368e-71e87a3fa34e@landley.net> References: <1466117661-22075-1-git-send-email-mcgrof@kernel.org> <1466117661-22075-3-git-send-email-mcgrof@kernel.org> <20160824203901.GT3296@wotan.suse.de> <20160825194133.GC3296@wotan.suse.de> <20160902235916.GO3296@wotan.suse.de> <20160903002014.GP3296@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160903002014.GP3296@wotan.suse.de> Sender: linux-doc-owner@vger.kernel.org To: "Luis R. Rodriguez" , Daniel Vetter , Mimi Zohar , Felix Fietkau , David Woodhouse , Roman Pen , Bjorn Andersson , Ming Lei , Andrew Morton , Michal Marek , Greg KH Cc: Linux Kernel Mailing List , Vikram Mulukutla , Stephen Boyd , Mark Brown , Takashi Iwai , Johannes Berg , Christian Lamparter , hauke@hauke-m.de, Josh Boyer , Dmitry Torokhov , jslaby@suse.com, Linus Torvalds , Andy Lutomirski , Wu Fengguang , rpurdie@rpsys.net, Jeff Mahoney , j.anaszewski@samsung.com, Abhay_Salunke@dell.com, Julia Lawall , Gilles.Muller@lip6.fr, nicolas.palix@imag.fr, Tom Gundersen , Kay Sievers List-Id: linux-serial@vger.kernel.org On 09/02/2016 07:20 PM, Luis R. Rodriguez wrote: > kernel_read_file_from_path() can try to read a file from > the system's filesystem. This is typically done for firmware > for instance, which lives in /lib/firmware. One issue with > this is that the kernel cannot know for sure when the real > final /lib/firmare/ is ready, and even if you use initramfs > drivers are currently initialized *first* prior to the initramfs > kicking off. Why? > During init we run through all init calls first > (do_initcalls()) and finally the initramfs is processed via > prepare_namespace(): What's the downside of moving initramfs cpio extraction earlier in the boot? I did some shuffling around of those code to make initmpfs work, does anybody know why initramfs extraction _before_ we initialize drivers would be a bad thing? (The cpio is in memory, either linked into the kernel or from the bootloader. No drivers are needed to extract it, that's sort of the point.) The only things I can think of are memory churn (large contiguous physical page allocations), or if a driver somehow got us access to more physical memory? Rob