Description of problem: Kernel fails to activate DMA on DVD drive Version-Release number of selected component (if applicable): 2.4.18-18.8.0 How reproducible: Fully Steps to Reproduce: 1.Create /etc/sysconfig/harddiskhdc and edit to enable and set dma on DVD drive: USE_DMA=1 EXTRA_PARAMS=-d1 2. Reboot PC 3.See failure in /var/log/messages Dec 20 09:29:09 Titanic hdparm: HDIO_SET_DMA failed: Operation not permitted Dec 20 09:29:09 Titanic hdparm: setting using_dma to 1 (on) Dec 20 09:29:09 Titanic rc.sysinit: Setting hard drive parameters for hdc: succeeded Dec 20 09:29:09 Titanic hdparm: using_dma = 0 (off) Actual results: hdparm always fials to set dma on hdc Expected results: dma should be settable. This is needed for acceptable DVD playback. Additional info: See attachment.
From the release notes: o DMA is disabled on CD-ROM drives in this release in a different but more reliable way than previously. If you are sure that your CD-ROM drive is capable of IDE DMA, place the following line in the /etc/modules.conf file: options ide-cd dma=1
Created attachment 88834 [details] dmesg
Thanks for your very quick response! "options ide-cd dma=1" in /etc/modules.conf works fine. Where should I have been looking to find this out for myself?
Quoting Arjan - "From the release notes:"