[linux-lvm] Filesystem corruption with LVM's pvmove onto a PV with a larger physical block size

[Stuart D. Gathman]

On Mon, 4 Mar 2019, Cesare Leonardi wrote:

> Today I repeated all the tests and indeed in one case the mount failed: after 
> pvmoving from the 512/4096 disk to the 4096/4096 disk, with the LV ext4 using 
> 1024 block size.
  ...
> The error happened where you guys expected. And also for me fsck showed no 
> errors.
>
> But doesn't look like a filesystem corruption: if you pvmove back the data, 
> it will become readable again:
  ...

THAT is a crucial observation.  It's not an LVM bug, but the filesystem
trying to read 1024 bytes on a 4096 device.  I suspect it could also
happen with an unaligned filesystem on a 4096 device.

-- 
 	      Stuart D. Gathman <stuart at gathman.org>
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.