The kernel first saw this disk as having 4096 logical block size:
# lsscs -gs
[6:0:2:0] disk HGST HUS726T4TAL4204 C430 /dev/sdd /dev/sg3 4.00TB
Then about a minute later it had a logical block size of 512 bytes after:
# sg_format --format --ffmt=1 --size=512 /dev/sg3
[The '--ffmt=1' option means fast format and it obviously doesn't visit
every block.] The sd driver was not amused and when I did:
# fdisk /dev/sdd
That xterm froze in an uninterruptible state and from another xterm I could
see the log being filled with:
[ 1004.409881] sd 6:0:2:0: [sdd] Unaligned partial completion (resid=3584,
sector_sz=4096)
Rebooted but that locked up the machine, power cycle ...
Doug Gilbert