Nm, user error. Should have been using 'losetup -o 8192 /dev/loop0 /dev/dm-1'. Thanks, Brendan On Fri, Jan 22, 2021 at 10:52 AM Brendan Boerner <bboerner.biz@xxxxxxxxx> wrote: > > How do I get bcache to completely give up access to a backing device > so I can mount it using losetup? > > My backing device is an lvm logical volume which I expanded in size. > > I want to mount it using losetup to use xfs_growfs however I can't > access the backing device: > > root@timber4:/var/log# umount /mnt/archives/ ; echo 1 > > /sys/block/bcache1/bcache/stop ; echo 1 > /sys/block/dm-1/bcache/stop > ; losetup -o 8192 /dev/loop0 /dev/vg-bfd02/archives_bc > -bash: /sys/block/dm-1/bcache/stop: No such file or directory > losetup: /dev/vg-bfd02/archives_bc: failed to set up loop device: > Device or resource busy > > I know in some cases udev is scurrying in and causing the cache to be > recreated but even immediately after the stop and before udev can get > in the backing device is still locked: > > Jan 22 11:48:33 timber4 kernel: [370093.820204] XFS (bcache1): > Unmounting Filesystem > Jan 22 11:48:33 timber4 kernel: [370093.830609] bcache: > bcache_device_free() bcache1 stopped > Jan 22 11:48:33 timber4 systemd[1]: Stopped File System Check on > /dev/disk/by-uuid/cb9c1149-73b8-4929-bcc6-d1599d41da73. > Jan 22 11:48:33 timber4 kernel: [370093.904348] bcache: > register_bcache() error /dev/dm-1: device busy > > I was able to do this in the past when I first started learning to use > bcache which is why this is especially perplexing. > > Suggestions? > > Thanks, > Brendan
