[linux-lvm] confused with lvm2 filter rules

[Heming Zhao]

Hello,

I met below filter action when executed 'vgextend'.
why the filter take no effect on executing pvcreate or vgcreate?

```
# ls -l /dev/disk/by-id/scsi-*
lrwxrwxrwx 1 root root 9 Jun  3 20:44 /dev/disk/by-id/scsi-360073a707 -> 
../../sda
lrwxrwxrwx 1 root root 9 Jun  3 20:44 /dev/disk/by-id/scsi-36007c0036 -> 
../../sdb
lrwxrwxrwx 1 root root 9 Jun  3 20:27 /dev/disk/by-id/scsi-3600b99ec4 -> 
../../sdc
# pvcreate /dev/disk/by-id/scsi-36073a707 /dev/disk/by-id/scsi-36007c0036
# pvs
   PV         VG Fmt  Attr PSize PFree
   /dev/sda      lvm2 ---  2.00g 2.00g
   /dev/sdb      lvm2 ---  2.00g 2.00g
# vgcreate vgtst /dev/disk/by-id/scsi-36073a707 
/dev/disk/by-id/scsi-36007c0036hy the filter take no effect on executing 
pvcreate or vgcreate?
# vgs
   VG    #PV #LV #SN Attr   VSize VFree
   vgtst   2   0   0 wz--n- 3.98g 3.98g
# vgextend vgtst /dev/disk/by-id/scsi-3600b99ec4
   Device /dev/disk/by-id/scsi-3600b99ec4 excluded by a filter.
# vgs
   VG    #PV #LV #SN Attr   VSize VFree
   vgtst   2   0   0 wz--n- 3.98g 3.98g

my enviroment:
# rpm -qa | grep lvm2
lvm2-clvm-2.02.180-8.16.x86_64
lvm2-cmirrord-2.02.180-8.16.x86_64
lvm2-2.02.180-8.16.x86_64

the filter rules:  (you can see all the disk in /dev/disk/by-id/ are 
rejected)
# grep filter /etc/lvm/lvm.conf | grep -v "#"
     filter = [ "r|/dev/.*/by-path/.*|", "r|/dev/.*/by-id/.*|", 
"r|/dev/fd.*|", "r|/dev/cdrom|", "a/.*/" ]
```


Thank you.
zhm