Bug 21

Hi,

I am using a self compiled Linux system and getting a strange error with mdev.

Linux 2.6.28
binutils 2.19
gcc 4.3.2
uClibc 0.9.30
(with following patch applied:
http://sources.busybox.net/index.py/trunk/uClibc/libc/sysdeps/linux/common/mknod.c?r1=23831&r2=24046)
busybox 1.12.4

The Linux hotplug system is configured to call mdev on any event.
# cat /proc/sys/kernel/hotplug 
/sbin/mdev

When I load the device-mapper kernel modul a device node is created:
# ls -la /dev/device-mapper 
crw-rw----    1 root     root      10,  60 Jan  8 10:05 /dev/device-mapper

But some thing is broken with this node:
# strace -f -estat64 ls /dev/device-mapper  
stat64("/dev/device-mapper", {st_mode=S_IFCHR|0660, st_rdev=makedev(2058, 753468), ...}) = 0

And dmsetup does not work:
# ln -sf /dev/device-mapper /dev/mapper/control
# dmsetup targets
/dev/mapper/control: open failed: No such device or address
Failure to communicate with kernel device-mapper driver.
Command failed

When I delete the device node and recreate it with either mknod or mdev -s,
everything works like expected:
# rm /dev/device-mapper 
# mdev -s
# strace -f -estat64 ls /dev/device-mapper
stat64("/dev/device-mapper", {st_mode=S_IFCHR|0660, st_rdev=makedev(10, 60), ...}) = 0
/dev/device-mapper
# dmsetup targets
crypt            v1.6.0
striped          v1.1.0
linear           v1.0.3
error            v1.0.1

A similar problem occured with busybox mknod applet _before_ I applied the uClibc patch mentioned above.

If any information is missing, don't hesitate to ask.

Thanks in advance
 Waldemar 

P.S.: I can provide a link to the qemu image on personal request.