[ltp] is Ultrabay hot swappable

[mario]

So, André Wyrwa wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
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> Hi,
>
>> /dev/hdc:
>>  setting using_dma to 1 (on)
>>  HDIO_SET_DMA failed: Operation not permitted
>>  using_dma    =  0 (off)
>>
>> This is after running hotswap.
>> The drives are swappable just fine.
>> Unfortunately no DMA on the hard drive translates into 2MB throughput.
>> This time i googled before i wrote, but to no avail.
>>
>> Has anybody figured out howto fix this?
>
> There's no known fix, yet.
>
> BTW: Did anyone ever try manually disabling DMA before running hotplug
> and then trying to reenable it afterwards?

Yup, i just did. Turning off DMA before hotswap produces this interaction:
[root@perky 18:31:46 ~]#hdparm -v /dev/hdc

/dev/hdc:
 multcount    =  0 (off)
 IO_support   =  0 (default 16-bit)
 unmaskirq    =  0 (off)
 using_dma    =  1 (on)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 65535/16/63, sectors = 117210240, start = 0
[root@perky 18:32:03 ~]#hdparm -d0 /dev/hdc

/dev/hdc:
 setting using_dma to 0 (off)
 using_dma    =  0 (off)
[root@perky 18:32:09 ~]#hotswap
hotswap 0.4.0
Copyright 2001 Tim Stadelmann
This program is free software, licensed under the conditions of the
GNU General Public License version 2, or (at your option), any later
version.


The following IDE device is currently configured:
HTS721060G9AT00
Do you want to remove this device? y
You can now remove the device from the module bay.

Would you like to insert an IDE device into the module bay? n
Aborting
[root@perky 18:32:31 ~]#hotswap
hotswap 0.4.0
Copyright 2001 Tim Stadelmann
This program is free software, licensed under the conditions of the
GNU General Public License version 2, or (at your option), any later
version.

There is currently no IDE device configured.  (Floppy disk drives,
batteries, and 'travel modules' are not managed by this utility.  If
you want to swap such a module, you should remove it now.)

Would you like to insert an IDE device into the module bay? y
Please insert the new device into the module bay and press RETURN.

Segmentation fault
[root@perky 18:32:51 ~]#hdparm -d1 /dev/hdc

After this hdparm goes some sort of timeout heaven and can't be killed:

 8245 pts/5    D+     0:00 hdparm -d1 /dev/hdc

Interesting thought though.

Got go reboot now :)

mario;>