From mboxrd@z Thu Jan 1 00:00:00 1970 From: William Wagner Date: Mon, 07 Mar 2011 18:52:35 +0000 Subject: [Buildroot] [PATCH 49/55] Improve handling of mdev/udev In-Reply-To: References: Message-ID: <4D752973.3090004@carallon.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 05/12/2010 20:53, Thomas Petazzoni wrote: > Yegor Yefremov introduced udev/mdev integration, but it relies on > devtmpfs and does not use tmpfs on /dev, which is the purpose of > mdev/udev. This commit improves how mdev and udev are handled in > Buildroot. > > At compile time, only a minimal /dev is created in the filesystem, > with only "console" and "null". This is done thanks to a small device > table in target/generic/device_table_mdev_udev.txt. This is done > directly at the configuration level (fs/Config.in). > > Moreover, at compile time, the mounting of a tmpfs filesystem in /dev > is enabled/disabled in /etc/inittab depending on whether udev/mdev are > used or not. This is done in target/generic/Makefile.in, together with > other hooks to tune the target filesystem (hostname, serial port, > etc.). > > At run time, what happens is : > > * inittab sysinit actions are executed. They do: remount the root > filesystem read/write, mount the proc filesystem, mount a tmpfs > filesystem in /dev, create the /dev/pts directory and then mount > all filesystems listed in fstab. > > * initialization scripts are started, with S10mdev or S10udev being > at the very beginning of the list of scripts to be executed. > > Between the moment at which a tmpfs filesystem is mounted in /dev and > the moment S10mdev or S10udev are executed, the /dev directory is > empty of devices. This is why the "null" device is no longer used to > redirect messages from sysinit actions. > > The kernel compilation code is improved to only enable devtmpfs in the > configuration when the devtmpfs method is used. udev/mdev do not > require devtmpfs, only tmpfs. > > Finally, the S10udev startup script is simplified, as it handled > unnecessary things: mount sysfs, mount a tmpfs filesystem in /dev/, > etc. > > Signed-off-by: Thomas Petazzoni Hi Thomas/Peter, What is the status of this patch? Will it or something similar get merged this development cycle. I'm looking to update to a newer buildroot version internally and I'll either need this patch or something I've written myself and would rather stay in sync with upstream. Thanks Will -- ------------------------------------------------------------------------ Will Wagner will_wagner at carallon.com Development Manager Office Tel: +44 (0)20 7371 2032 Carallon Ltd, Studio G20, Shepherds Building, Rockley Rd, London W14 0DA ------------------------------------------------------------------------