07.05.2021 15:31, Zdenek Kabelac wrote:
Dne 07. 05. 21 v 12:31 Michael Tokarev napsal(a):
...
sz=$(blockdev --getsize /dev/loop0) dmsetup create base --table "0 $sz snapshot-origin /dev/loop0" # and now the crash mkfs.ext4 /dev/mapper/base
Yes reproducible - can you please open BZ report here: https://bugzilla.redhat.com/enter_bug.cgi?product=LVM%20and%20device-mapper
Ok, will do, thanks!
I assume you are aware you are trying to using snapshot target in wrong way, but it should not be crashing kernel.
Actually I'm not aware about the wrong way. The documentation is a bit lacking in this area. There are a few (maybe 2 or 3) guides describing the steps to do, most involves first using an 1:1 linear table, next replacing it on-the-fly with snapshot-origin table, but nowhere it is told that I can't create snapshot-origin directly, or that I need at least one snapshot device, or that the origin of the snapshot-origin table should be a dm device, or many many other variations. I just tried to create a snapshot to be able to revert changes if something goes wrong, and since I don't use lvm I thought that plain dmsetup should do, but discovered that it doesn't quite work and it actually is a dangerous thing to use.. :) Thanks! /mjt -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel
