From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040312 Description of problem: These two devices don't work together unless booted with "hdd=ide-scsi": - class: CDROM bus: IDE detached: 0 device: hdc driver: ignore desc: "LG DVD-ROM DRD-8160B" - class: CDROM bus: IDE detached: 0 device: hdd driver: ignore desc: "SONY CD-RW CRX175E2" - Version-Release number of selected component (if applicable): kernel-2.6.4-1.298 How reproducible: Always Steps to Reproduce: 1.Boot without "hdd=ide-scsi". 2.Look in /var/log/messages for errors+reset during ide device probe. 3.Boot with "hdd=ide-scsi". 4.Look in /var/log/messages for no error in ide device probe. Actual Results: Without hdd=ide-scsi: error messages during ide device probe, as in attachment. With hdd=ide-scsi: no errors reported. Expected Results: No errors in either case; no need for hdd=ide-scsi. Additional info: When booted with hdd=ide-scsi: # cd /proc/ide # cat hdc/settings name value min max mode ---- ----- --- --- ---- current_speed 66 0 70 rw dsc_overlap 1 0 1 rw ide-scsi 0 0 1 rw init_speed 66 0 70 rw io_32bit 0 0 3 rw keepsettings 0 0 1 rw nice1 1 0 1 rw number 2 0 3 rw pio_mode write-only 0 255 w unmaskirq 0 0 1 rw using_dma 1 0 1 rw # cat hdd/settings name value min max mode ---- ----- --- --- ---- current_speed 34 0 70 rw ide-scsi 0 0 1 rw init_speed 34 0 70 rw io_32bit 0 0 3 rw keepsettings 0 0 1 rw nice1 1 0 1 rw number 3 0 3 rw pio_mode write-only 0 255 w unmaskirq 0 0 1 rw using_dma 1 0 1 rw # ----- BIOS IDE device detection says hdc(DVD) is UDMA33, and hdd(CD-R) is mwDMA.
Created attachment 98985 [details] /var/log/messages errors without hdd=ide-scsi
PIO v DMA problem at a first guess but very strange indeed.
Motherboard chipset is i845 (piix ICH2), whose IDE timings seem to be non-adjustable once the ATA mode is set. [How can I force a change from PIO mode 4 (mwDMA2) to PIO mode 3 (mwDMA1)? Or set the address-setup time to 120ns absolutely, like on VIA chipsets?] Workaround: boot with a CD-ROM or CD-RW [either blank or already recorded] in hdd (SONY CRX175E2). Then there are no errors reported in /var/log/messages, even without hdd=ide-scsi, and burning a CD-RW works using "cdrecord dev=/dev/hdd ..." So it looks like a device-specific problem [slow or bad SONY].
any better with the 2.6.9 update ?
Hardware has changed, the problem does not occur with new hardware under kernel-2.6.9-1.6_FC2. The old hardware is unavailable for testing. Configuration is now: hdc: PLEXTOR DVDR PX-712A, ATAPI CD/DVD-ROM drive [replaces LG DVD-ROM DRD-8160B] hdd: SONY CD-RW CRX175E2, ATAPI CD/DVD-ROM drive [same as before] In addition to software updates, this could cast some doubt on the hardware behavior of the old LG DVD-ROM when used as master with a slave present.