Bug#522091: udev: unable to make hdd go standby

Bug#522091: udev: unable to make hdd go standby

[Marco d'Itri]

[-- Attachment #1: Type: text/plain, Size: 792 bytes --]

Indeed a change event is generated when I run hdparm -y /dev/sda.
Does anybody know why, and a workaround?

----- Forwarded message from John van der Kamp <john@kirika.demon.nl> -----

From: John van der Kamp <john@kirika.demon.nl>
To: Debian Bug Tracking System <submit@bugs.debian.org>
Subject: Bug#522091: udev: unable to make hdd go standby

Package: udev
Version: 0.140-1
Severity: normal


Normally, I set a harddisk to standby using hdparm (hdparm -y /dev/sda)
on startup (rc.local), but udev immediately spins the harddisk backup.
Only after stopping udev would the harddisk stay in standby mode. I had
no problems with udev 0.125 with this sofar. Since I have 0.140 this
problem arose.

Regards,

John

----- End forwarded message -----

-- 
ciao,
Marco

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 197 bytes --]

Re: Bug#522091: udev: unable to make hdd go standby

[Kay Sievers]

> From: John van der Kamp <john@kirika.demon.nl>
>
> Normally, I set a harddisk to standby using hdparm (hdparm -y /dev/sda)
> on startup (rc.local), but udev immediately spins the harddisk backup.
> Only after stopping udev would the harddisk stay in standby mode. I had
> no problems with udev 0.125 with this sofar. Since I have 0.140 this
> problem arose.

On Tue, Mar 31, 2009 at 20:25, Marco d'Itri <md@linux.it> wrote:
> Indeed a change event is generated when I run hdparm -y /dev/sda.
> Does anybody know why, and a workaround?

Because hdparm opens the device writable, while it should probably
only do it with O_RDONLY. Recent udev versions check the device again,
when it was opened for writing.

Kay