possible bug: dparm using_dma flag reset automatically reset

Philippe A. futhark77 at gmail.com
Sun Apr 23 04:53:14 UTC 2006


I came to realize that ejecting my dvd drive automatically resets the
using_dma flag. For some time, I had to think to manually re-enable the dma
setting if I didn't want to end up burning at 1X in K3B. I eventually found
the problem to be happening when using "/dev/dvd" as a parameter to hdparm,
but not when using "/dev/hdc".

My drive is an one week old LG HL-DT-ST DVDRAM GSA-H10A. I also have an old
Hewlett-Packard CD-Writer Plus 8200 installed as the slave on the same IDE
channel. I am running kernel 2.6.15-1.1833_FC4 under Fedora Core 4.

Below is a mini script showing using_dma getting reset immediately after
eject. Replace /dev/dvd by /dev/hdc and the problem is gone! Does that ring
a bell to anyone?

$ sudo hdparm -c1 -d1 -u1 -a8 -k1 /dev/dvd && hdparm -v /dev/dvd && sudo
eject && hdparm -v /dev/dvd && sleep 10 && eject -T && hdparm -v /dev/dvd

/dev/dvd:
 setting fs readahead to 8
 setting 32-bit IO_support flag to 1
 setting unmaskirq to 1 (on)
 setting using_dma to 1 (on)
 setting keep_settings to 1 (on)
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  1 (on)
 readahead    =  8 (on)

/dev/dvd:
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  1 (on)
 readonly     =  0 (off)
 readahead    =  8 (on)
 HDIO_GETGEO failed: Invalid argument

/dev/dvd:
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  0 (off)
 keepsettings =  1 (on)
 readonly     =  0 (off)
 readahead    =  8 (on)
 HDIO_GETGEO failed: Invalid argument
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.fedoraproject.org/pipermail/users/attachments/20060423/75388a00/attachment-0002.html 


More information about the users mailing list