Re: kern/48849: root mirror raid fails on shutdown

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

It seems I no longer have a test case: I rebuilt the raid, tried a kernel
with the above patch, the box hung on shutdown. I power-cycled, reverted
the patch, and since then raid7 has remained optimal over many reboots
and the old kernel:

...
unmounting 0xfffffe8107159008 / (/dev/raid7a)...
Entering dounmount / (/dev/raid7a)...
VFS_SYNC(/) = 0
VFS_UNMOUNT(/) = 16 
cgd0: detached
raid4: detached
raid4: detached
dk11 at wd1 (df25cd88-6326-11e3-8f70-10bf48bd3389) deleted
dk11: detached
dk4 at wd0 (80706d97-e1f8-11e3-9080-10bf48bd3389) deleted
dk4: detached
unmounting 0xfffffe8107159008 / (/dev/raid7a)...
Entering dounmount / (/dev/raid7a)...
VFS_SYNC(/) = 0
VFS_UNMOUNT(/) = 16 
forcefully unmounting / (/dev/raid7a)...
Entering dounmount / (/dev/raid7a)...
VFS_SYNC(/) = 0
VFS_UNMOUNT(/) = 0 forced
called vfs_hooks_unmount(/)
Successfully exiting dounmount / (/dev/raid7a)...
raid7: detached
raid7: detached
dk7 at wd1 (df25cd61-6326-11e3-8f70-10bf48bd3389) deleted
dk7: detached
dk0 at wd0 (80706d87-e1f8-11e3-9080-10bf48bd3389) deleted
dk0: detached
wd1: detached
wd0: detached

No attempt to write a component?

The history of the box might be important:
It had a working mirror. I replaced one of the disks with a new one.
After that point it the raid7 failed. Is it the case the raidframe
has to write a component label once, but not subsequently? and that it
managed it once with hannken@' patch?