Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=2ac217d408470dcec... Commit: 2ac217d408470dcecb69b83d9cbf7a254747fa5b Parent: baf9ef2047675279c72f27abeb2c328f5de2c78d Author: Peter Rajnoha prajnoha@redhat.com AuthorDate: Fri May 3 13:20:07 2013 +0200 Committer: Peter Rajnoha prajnoha@redhat.com CommitterDate: Fri May 3 13:55:53 2013 +0200

udev: fire pvscan --cache properly on CHANGE event for MD devices

Commit 756bcabbfe297688ba240a880bc2b55265ad33f0 restricted the situations at which the LVM autoactivation fires - only on ADD event for devices other than DM. However, this caused a problem for MD devices...

MD devices are activated in a very similar way as DM devices: the MD dev is created on first appeareance of MD array member (ADD event) and stays *inactive* until the array is complete. Just then the MD dev turns to active state and this is reported to userspace by CHANGE event.

Unfortunately, we can't differentiate between the CHANGE event coming from udev trigger/WATCH rule and CHANGE event coming from the transition to active state - MD would need to add similar logic we already use to detect this in DM world. For now, we just have to enable pvscan --cache on *all* CHANGE events for MD so the autoactivation of the LVM volumes on top of MD works.

A downside of this is that a spurious CHANGE event for MD dev can cause the LVM volumes on top of it to be automatically activated. However, one should not open/change the device underneath until the device above in the stack is removed! So this situation should only happen if one opens the MD dev for read-write by mistake (and hence firing the CHANGE event because of the WATCH udev rule), or if calling udev trigger manually for the MD dev.

(No WHATS_NEW here as this fixes the commit mentioned above and which has not been released yet.) --- udev/69-dm-lvm-metad.rules.in | 1 + 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/udev/69-dm-lvm-metad.rules.in b/udev/69-dm-lvm-metad.rules.in index 66c58b3..a0e48a1 100644 --- a/udev/69-dm-lvm-metad.rules.in +++ b/udev/69-dm-lvm-metad.rules.in @@ -21,6 +21,7 @@ SUBSYSTEM!="block", GOTO="lvm_end" ENV{ID_FS_TYPE}!="LVM2_member|LVM1_member", GOTO="lvm_end"

ACTION=="remove", GOTO="lvm_scan" +ACTION=="change", KERNEL=="md[0-9]*", GOTO="lvm_scan"

# If the PV is not a dm device, scan only after device addition (ADD event) KERNEL!="dm-[0-9]*", ACTION!="add", GOTO="lvm_end"