tree c095e7185a535448eb9f0257b16c77bf279a9d04
parent 6a2cf8d3663e13e19af636c2a8d92e766261dc45
author Jeremy Cline <jeremy@jcline.org> 1520372852 +0000
committer Martin K. Petersen <martin.petersen@oracle.com> 1520392069 -0500

scsi: sd: Keep disk read-only when re-reading partition

If the read-only flag is true on a SCSI disk, re-reading the partition
table sets the flag back to false.

To observe this bug, you can run:

1. blockdev --setro /dev/sda
2. blockdev --rereadpt /dev/sda
3. blockdev --getro /dev/sda

This commit reads the disk's old state and combines it with the device
disk-reported state rather than unconditionally marking it as RW.

Reported-by: Li Ning <lining916740672@icloud.com>
Signed-off-by: Jeremy Cline <jeremy@jcline.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>