Hi Neil, I'd like to have your advice about destroying an array created by open at close time if not configured, rather than waiting for a ioctl or a sysfs configuration. This would allow to get rid of the inactive md devices created by an "accidental" open. On the Linux distribution embedded in LaCie NAS, we are able to observe the following scenario: 1. A RAID array is stopped with a command such as mdadm --stop /dev/mdx. 2. The node /dev/mdx is still available because not removed by mdadm at stop. 3. /dev/mdx is opened by a process such as udev or mdadm --monitor. 4. An inactive RAID array mdx is created and a "add" uevent is broadcasted to userland. It is let to userland to understand that this event must be discarded. You have to admit that this behaviour is at best awkward :) I read the commit d3374825ce57 "md: make devices disappear when they are no longer needed" in which you express some concerns about an infinite loop due to udev always opening newly created devices. Is that still actual ? In your opinion, how could we get rid of an inactive RAID array created by open ? Maybe we could switch the hold_active flag from UNTIL_IOCTL to 0 after some delay (enough to prevent udev from looping) ? In addition, maybe we could remove the device node from mdadm --stop ? Or maybe something else :) If you are interested by any of this solutions or one of yours, I'll be happy to work on it. Thanks in advance for your thoughts, Simon
Attachment:
signature.asc
Description: Digital signature
