dmraid causes udev event feedback loop in Lucid
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
dmraid (Ubuntu) |
Fix Released
|
High
|
Unassigned | ||
Lucid |
Fix Released
|
High
|
Unassigned |
Bug Description
Binary package hint: dmraid
Trying to boot Karmic Alpha 3 my system hangs for 3 minutes in the initramfs, then finally times out waiting for udev to settle and drops to a busybox shell. After much investigation the the problem seems to be a udev event infinite feedback loop. Every time udev gets an event, it runs dmraid-activate, which in turn runs dmraid with the -Z switch. This appears to tell it to remove the partitions from the underlying real disk device which causes a change event to occur. I am not sure why, but in 9.10, only one change event it generated according to udevadm monitor. If dmraid-activate is run on sda, then sda gets a change event, which it appears udev is smart enough not to recursively process. Likewise, when run on sdb, only an sdb change event occurs. In Karmic Alpha 3, a change event is generated for BOTH sda and sdb when dmraid-activate is run on either one, so when sda is processed, it generates a change on sdb, which is then processed and causes a change in sda, which... and so on...
I think the way to fix this is to change the dmraid udev rule to only activate on add events, not change events, but I am not sure.
Related branches
- Scott James Remnant (Canonical): Pending requested
- Ubuntu branches: Pending requested
-
Diff: 25 lines (+8/-1)2 files modifieddebian/changelog (+7/-0)
debian/dmraid.udev (+1/-1)
tags: | added: kernel-series-unknown |
tags: | removed: kernel-series-unknown |
tags: | added: regression-potential |
Changed in dmraid (Ubuntu): | |
importance: | Undecided → High |
milestone: | none → ubuntu-10.04 |
status: | Confirmed → Triaged |
Do you mean Lucid (10.04) and not Karmic (9.10)?