[ltp] Re: enabling protect file for hdaps on t61

[Vincent C Jones]

On Mon, 2008-02-11 at 01:00 +0100, Rolf Kutz wrote:
> On 10/02/08 00:18 +0100, Elias Oltmanns wrote:
> >
> >Is this with libata (and ata_piix in particular)? Try the following
> >experiment:
> 
> This is an SATA hdd, maybe that's the difference.
> ata_piix is just for the DVD.:
> # lsmod|grep ata
> ata_piix               23236  0
> libata                174960  2 ahci,ata_piix
> scsi_mod              179192  4 sd_mod,sg,sr_mod,libata
> 
> >Switch to single user mode and remount the partitions read only. Perform
> >the following commands:
> >
> ># cat some-big-file > /dev/null &
> ># echo 1 > /sys/block/sda/queue/protect
> > 
> >Repeat the second one several times while the read operation of the
> >first one is in progress. Make sure that you actually hear the drive
> >park heads and resume normal operation. My system freezes after the
> >third park command at the latest.
> 
> Done that and it didn't freeze the system even
> after ten times. That doesn't mean that there
> isn't a bug. It just doesn't trigger on this
> system.
> 
> regards, Rolf

SATA drive here as well (7675 X61, AHCI mode, SuSE 10.3, 2.6.24 with
SuSE, acpi, protect, & tp_smapi patches applied) and I have no problem
invoking a freeze. What is your magic incantation to avoid the problem?
I really would like to get HDAPS back...

Vince