Re: Is controlling DVD speeds via SET_STREAMING supported?

[Jens Axboe <axboe@suse.de>]

(don't trim the cc list, please!!)

On Sun, Nov 28 2004, Pasi Savolainen wrote:
> * Jens Axboe <axboe@suse.de>:
> >> > I modified your speed-1.0 to open device O_RDWR, didn't help.
> >> > I modified it to also dump_sense after CMD_SEND_PACKET, it's just
> >> > duplicate packet.
> >> 
> >> No this will definitively not solve this issue. I will try to check this
> >> in the kernel, but because I'm not a kernel developer I will CC Jens
> >> Axboe. Maybe he can help?
> >
> > Just fix the permission on the special file. Additionally, the program
> > must open the device O_RDWR.
> 
> (under 2.6.10-rc2-mm1)
> I ran speed-1.0 program as root and also modified to open the device
> file as O_RDWR. This didn't help, it still reports same error.

Ehm I don't see how that is possible, since that kernel definitely
contains SET_STREAMING as a write safe command. Are you 110% sure you
are running the kernel you think you are?

> Booted into 2.4.28, speed-1.0 didn't do the trick there either. 'sense'
> reported was 00.00.00 though.

Any dmesg errors from 2.4.28? The sense reporting might be a bit broken
there, but if you don't set cgc->quiet it should report the error in the
kernel ring buffer at least.

-- 
Jens Axboe