Re: 2.6.18-rc2, problem to wake up spinned down drive?

[Bill Davidsen <davidsen@tmr.com>]

Tejun Heo wrote:
> Harald Dunkel wrote:
>> Tejun Heo wrote:
>>> Can you try the following instead of hdparm?
>>>
>>> echo 1 > /sys/bus/scsi/devices/1:0:0:0/power/state
>>>
>>> It will make libata involved in putting the disk to sleep and waking it
>>> up, and, when waking, it will kick the drive in the ass by resetting the
>>> channel.  Please try with the latest -rc kernel.
>>>
>>
>> Sorry to say, but this did not work:
>>
>> # echo 1 > /sys/bus/scsi/devices/0:0:0:0/power/state
>> bash: echo: write error: Invalid argument
>> # ll !$
>> ll /sys/bus/scsi/devices/0:0:0:0/power/state
>> -rw-r--r-- 1 root root 0 Aug  1 20:00 
>> /sys/bus/scsi/devices/0:0:0:0/power/state
>> # cat !$
>> cat /sys/bus/scsi/devices/0:0:0:0/power/state
>> 0
>> # uname -a
>> Linux bugs 2.6.18-rc3 #2 PREEMPT Sun Jul 30 16:26:22 CEST 2006 i686 
>> GNU/Linux
> 
> You probably should do 'echo -n 1', the parsing function is pretty picky.
> 
Given that the data from the "cat" of state returned a zero with 
newline, perhaps unreasonably picky. On a Fedora kernel it just doesn't 
seem to work for SATA drives, sample size = 1.

-- 
Bill Davidsen <davidsen@tmr.com>
   Obscure bug of 2004: BASH BUFFER OVERFLOW - if bash is being run by a
normal user and is setuid root, with the "vi" line edit mode selected,
and the character set is "big5," an off-by-one errors occurs during
wildcard (glob) expansion.