When busybox is used for device management, kernel needs to support
older/obsolete mechanism via CONFIG_UEVENT_HELPER and
CONFIG_UEVENT_HELPER_PATH to enable /proc/sys/kernel/hotplug but this
would require kernel defconfig change and will always be needed when
mdev is used, intead run it in daemon mode
Update mdev init script to run mdev in daemon mode
(From OE-Core rev: f9e84b31ea4afe566c76dcdea25960478cd36ecc)
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
echo would fail if /sys is not mounted and boot would abort
(From OE-Core rev: b8901336e72639342a1d784557043fa47a9d90ff)
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
During boot, there is a brief window during which /dev/initctl is
missing, which breaks initscripts that would need to access it. This
occurs because /etc/init.d/mountall.sh (rcS.d/S02...) attempts to ensure
/dev/initctl is present, but /etc/init.d/mdev (rcS.d/S06...) mounts over
/dev and clobbers the work done by mountall, and then does not wait
synchronously until initctl is ready before continuing.
To close this window, in /etc/init.d/mdev, we check whether /dev/initctl
is present, and if not, we remove it and recreate it. This is the same
thing that is done by /etc/init.d/mountall.sh, and we have verified that
any writers of /dev/initctl will wait synchronously until sysvinit
notices the change in fd and does the read, so no race exists.
(From OE-Core rev: 53543363a8ab4424c17ed7aec0e8aefc4df86b3d)
Signed-off-by: Richard Tollerton <rich.tollerton@ni.com>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
/dev/mdev.seq exists to synchronize concurrently running instances of
mdev and to ensure that they execute in the proper order. Without this
synchronization, it is possible to have inconsistent mount points, to
leak device nodes, or to have a node erroneously removed in rapid
hotplug scenarios.
Enable the use of mdev.seq by creating an empty /dev/mdev.seq at boot.
(From OE-Core rev: 3b256653ae9ab2cf56b21cb82a8bd2a562397b27)
Signed-off-by: Richard Tollerton <rich.tollerton@ni.com>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Otherwise, users cannot use named semaphores or shared memory.
(From OE-Core rev: a8f35be467836d8fa0bc8f8e85eba6f89a13f087)
Signed-off-by: Richard Tollerton <rich.tollerton@ni.com>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This changes the packaging only if the configuration used has mdev
support enabled.
(From OE-Core rev: 82b163043aa53488a03bb3de3a78e5b6eeb76019)
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
