Opening as a lvm2 bug, but it may be something in device-mapper instead.

Last night, I did a yum update on my main workstation before shutting it down. This morning, it was unable to boot. The LVM2 device scan couldn't find the PVs. When it came up to the rescue prompt, I ran "pvs" and got a series of errors:

     Internal error: LV xxxxx/yyyyy has unknown feature flags: 0

...where xxxxxx was the VG and yyyyyy were some of the LVs. Unfortunately, I wasn't able to get a copy of the full error messages.

I ended up booting to a live usb stick and downgraded the device-mapper-* and lvm2-* packages that had gotten upgraded and now it boots fine again.

The packages installed when it failed were:

Jan 28 21:24:45 Updated: device-mapper-1.02.93-1.fc21.x86_64
Jan 28 21:24:46 Updated: device-mapper-libs-1.02.93-1.fc21.x86_64
Jan 28 21:24:47 Updated: device-mapper-event-libs-1.02.93-1.fc21.x86_64
Jan 28 21:24:52 Updated: device-mapper-event-1.02.93-1.fc21.x86_64
Jan 28 21:24:52 Updated: lvm2-libs-2.02.115-1.fc21.x86_64
Jan 28 21:24:57 Updated: lvm2-2.02.115-1.fc21.x86_64
Jan 28 21:24:58 Updated: device-mapper-devel-1.02.93-1.fc21.x86_64

...I downgraded to:

Jan 29 07:10:06 Installed: device-mapper-1.02.90-1.fc21.x86_64
Jan 29 07:10:21 Installed: device-mapper-libs-1.02.90-1.fc21.x86_64
Jan 29 07:10:22 Installed: device-mapper-event-libs-1.02.90-1.fc21.x86_64
Jan 29 07:10:33 Installed: device-mapper-event-1.02.90-1.fc21.x86_64
Jan 29 07:10:36 Installed: lvm2-libs-2.02.111-1.fc21.x86_64
Jan 29 07:10:40 Installed: lvm2-2.02.111-1.fc21.x86_64
Jan 29 07:10:41 Installed: device-mapper-devel-1.02.90-1.fc21.x86_64