Bug 490959

+++ This bug was initially created as a clone of Bug #481561 +++

Created an attachment (id=329975)
patch with fix

Description of problem:

Having /dev/md_d0 in /etc/mdadm.conf, incremental assembly
with mdadm -I --auto=yes fails.
This is specific for components with super-minor 0.
The bug affects array assembly by udev after boot, in which
case device numbers 9, 0 are assigned in place of correct
254, 0.

Version-Release number of selected component (if applicable):

mdadm-2.6.7-1.fc10

How reproducible:

always

Steps to Reproduce:

1. create linux array with partitions having minor
   number 0 (e.g. use /dev/md_d0 name)
2. craete mdadm.conf record for the array with
   name /dev/md_d0 indicating partitionable array
3. reboot 
  
Actual results:

Array assembled by udev has major number 9, minor
number 0, device file /dev/md0 -> not partionable 

Expected results:

Array is assembled with file /dev/md_d0, maj.
number 254, min. number 0.

Additional info:

I am adding patch which should fix it.

--- Additional comment from rvykydal on 2009-01-26 06:54:47 EDT ---

Created an attachment (id=329976)
reproducer session without and with patch from description

--- Additional comment from jwilson on 2009-02-24 11:42:12 EDT ---

Hm... Wondering if this is related to something I'm seeing too... F10 install originally, upgraded to rawhide, now gets this on boot initially for its md devices:

# cat /proc/mdstat 
Personalities : [raid1] [raid0] 
md126 : active raid1 sda3[0]
      22531072 blocks [2/1] [U_]
      
md127 : inactive sda7[0]
      25366528 blocks
       
md0 : active raid1 sda2[0] sdb1[1]
      200704 blocks [2/2] [UU]
      
md3 : inactive sdb6[1](S)
      25366528 blocks
       
md2 : inactive sdb2[1](S)
      22531072 blocks
       
md1 : active raid1 sda5[0] sdb3[1]
      22531008 blocks [2/2] [UU]
      
unused devices: <none>



The expected layout is:

# cat /proc/mdstat 
Personalities : [raid1] [raid0] 
md0 : active raid1 sda2[0] sdb1[1]
      200704 blocks [2/2] [UU]
      
md3 : inactive sda7[0] sdb6[1]
      50733056 blocks
       
md2 : active raid1 sda3[0] sdb2[1]
      22531072 blocks [2/2] [UU]
      
md1 : active raid1 sda5[0] sdb3[1]
      22531008 blocks [2/2] [UU]
      
unused devices: <none>


Sometimes md0 gets screwed up too. All the arrays are properly defined in /etc/mdadm.conf, so far as I can tell. Seems perhaps the arrays are being started in the initrd before all the components have actually been found, then the rest get found by udev or something (I get spew about this just after 'starting udev').

--- Additional comment from dledford on 2009-03-18 13:13:10 EDT ---

Jared, your issue is different.  Your issue is a duplicate of bug 488038.

--- Additional comment from dledford on 2009-03-18 13:16:52 EDT ---

Rydek, this bug is specific to mdadm-2.6.7-1, which is no longer in rawhide.  Instead, mdadm-3.0 is in rawhide, and this no longer applies to that version of mdadm (mdadm 3.0 doesn't even make partitionable arrays any more, instead it uses the kernel's built in support for dealing with partitions on generic block devices to get partitionable arrays instead, so all arrays with mdadm 3.0 are now normal arrays).

However, this problem does still exist in F10/F9, and I can't upgrade those to mdadm-3.0, so I'm moving it to F10 and cloning for F9.