Re: 2.6.27.10: ata1.00: HPA detected: current 293044655, native 293046768

[Robert Hancock <hancockr@shaw.ca>]

Justin Piszcz wrote:
> On one system, two Raptor 150s:
> 
> [    0.739402] ata1.00: HPA detected: current 293044655, native 293046768
> [    0.739491] ata1.00: ATA-7: WDC WD1500ADFD-00NLR5, 21.07QR5, max 
> UDMA/133
> [    0.739577] ata1.00: 293044655 sectors, multi 0: LBA48 NCQ (depth 31/32)
> [    0.742454] ata1.00: configured for UDMA/133
> 
> [    1.059146] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
> [    1.061406] ata2.00: ATA-7: WDC WD1500ADFD-00NLR5, 21.07QR5, max 
> UDMA/133
> [    1.061494] ata2.00: 293046768 sectors, multi 0: LBA48 NCQ (depth 31/32)
> [    1.064360] ata2.00: configured for UDMA/133
> 
> Two disks in a RAID-1 (mdadm) configuration, how come the first one
> has an issue w/HPA as the firmware of both disks is the same..?
> 
> l1:~# smartctl -a /dev/sda | grep -i bytes
> User Capacity:    150,038,863,360 bytes
> l1:~# smartctl -a /dev/sdb | grep -i bytes
> User Capacity:    150,039,945,216 bytes
> l1:~#
> 
> Why does this occur?

Presumably somebody or something set up a host protected area on one 
drive and not the other.. I believe there are some utilities out there 
that can be used to disable the HPA and allow the full capacity to be used.