MCP55 SATA data corruption in FreeBSD 7

[Daniel Eriksson]

I am having problems with silent data corruption on (some) drives
connected to an MCP55 SATA controller.

I have two servers, both running RELENG_7_0/amd64. One has the 570 Ultra
chipset, the other has 570 SLI. Both chipsets have the MCP55 SATA
controller.

The server with 570 Ultra chipset has a bunch of older 250GB SATA-150
drives hooked up to the MCP55 controller and it is working just fine.
The server with 570 SLI chipset has a bunch of new SATA-300 drives
hooked up to the MCP55 controller and it is giving me silent data
corruption (easily detectable by running ZFS scrub, every time I run it
new checksum errors show up). I know the drives are good because when
they are hooked up to another controller they work just fine.

Unfortunately the drives does not have a jumper for setting SATA-150
speed (they are Samsung 1 TB drives), and trying to force the drives to
SATA-150 speed with the "patch" provided by the manufacturer does not
seem to work (the drives still negotiate SATA-300 speed). I will try to
get my hands on another older SATA-150 drive (or a new that can be
jumpered) to verify if the culprit is the MCP55 revision (see below) or
the interface speed.


NOT working (570 SLI)
---------------------
atapci1 at pci0:0:5:0:     class=0x010185 card=0x72501462 chip=0x037f10de
rev=0xa2 hdr=0x00
    vendor     = 'Nvidia Corp'
    device     = 'MCP55 SATA Controller'
    class      = mass storage
    subclass   = ATA

Working (570 Ultra)
-------------------
atapci1 at pci0:0:5:0:     class=0x010185 card=0xcb8410de chip=0x037f10de
rev=0xa3 hdr=0x00
    vendor     = 'Nvidia Corp'
    device     = 'MCP55 SATA Controller'
    class      = mass storage
    subclass   = ATA

This is most likely related to kern/120296
(http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/120296) and kern/121396
(http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/121396).


If someone else is having data corruption problems with drives connected
to an MCP55 controller it might be worth testing if limiting the drives
to SATA-150 makes a difference. It will most likely take me a while
before I can verify this.

---
Daniel Eriksson (http://www.toomuchdata.com/)