lvs

/dev/vm_backups/backup read failed after 0 of 4096 at 995903864832: Input/output error
/dev/vm_backups/backup read failed after 0 of 4096 at 995903922176: Input/output error
/dev/vm_backups/backup read failed after 0 of 4096 at 0: Input/output error
/dev/vm_backups/backup read failed after 0 of 4096 at 4096: Input/output error

dmsetup remove vm_backups-backup

or:

vgreduce –removemissing