Multipath not showing correct RO/RW status

Issue

• The SAN device was put into read only mode by storage team. Then we had rescanned the devices reload multipath. Kernel logging confirms read only mode (Write protect is on). But multipath still shows RW status and doesn't change to RO.

  $ cat /sys/block/sdac/ro = 1
  $ cat /sys/block/sded/ro = 1
  $ cat /sys/block/sdif/ro = 1
  $ cat /sys/block/sdmg/ro = 1
  
  $ multipath -ll mpathec
  mpathec (123456789000292601779533031351222) dm-19 EMC,SYMMETRIX
  size=16G features='0' hwhandler='0' wp=rw          <---
  `-+- policy='queue-length 0' prio=1 status=active
    |- 0:0:0:16 sdac  65:0    active ready running
    |- 0:0:1:16 sded 70:128  active ready running
    |- 1:0:0:16 sdif 132:16  active ready running
    `- 1:0:1:16 sdmg 65:400  active ready running
  

• The same issue is observed when device status is changed from RO to RW, i.e. dm-multipath was still listing the devices in RO state even when the SAN team had changed path status to RW