I added append = "ide2=ata66 hdc=ide-scsi" to my lilo.conf. SCSI emulation for my CD-Writer and UDMA for my Promise Ultra 100. With vanilla-souces-2.4.20 everything works the way it should. dmesg output: Kernel command line: BOOT_IMAGE=Linux_old ro root=2105 ide2=ata66 hdc=ide-scsi ide_setup: ide2=ata66 ide_setup: hdc=ide-scsi Initializing CPU#0 <snip> PDC20268: chipset revision 2 PDC20268: not 100% native mode: will probe irqs later PDC20268: (U)DMA Burst Bit ENABLED Primary MASTER Mode Secondary MASTER Mode. PDC20268: ATA-66/100 forced bit set (WARNING)!! ide2: BM-DMA at 0x6400-0x6407, BIOS settings: hde:pio, hdf:pio ide3: BM-DMA at 0x6408-0x640f, BIOS settings: hdg:pio, hdh:pio SCSI emulation is also setup properly. Now with gentoo-sources: Kernel command line: BOOT_IMAGE=Linux ro root=2105 ide2=ata66 hdc=ide-scsi Initializing CPU#0 <snip> PDC20268: chipset revision 2 PDC20268: not 100% native mode: will probe irqs later PDC20268: (U)DMA Burst Bit ENABLED Primary MASTER Mode Secondary MASTER Mode. ide2: BM-DMA at 0x6400-0x6407, BIOS settings: hde:pio, hdf:pio ide3: BM-DMA at 0x6408-0x640f, BIOS settings: hdg:pio, hdh:pio Note that the lines ide_setup: ide2=ata66 ide_setup: hdc=ide-scsi are missing here. The two kernels are configured in the exact same way regarding SCSI emulation and Promise chip support. Reproducible: Always Steps to Reproduce: 1. Compile IDE CD-ROM support into the kernel 2. add hdx=ide-scsi to the kernel command line (where hdx is your cd-writer) Actual Results: The cd-writer hdx uses the IDE CD-ROM driver Expected Results: The cd-writer should be ignored by the IDE CD-ROM driver
I am using the same Gentoo sources and I know that hdb=ide-scsi works for me via grub. The cdrom comes up as scsi. When I remove that option then the cdrom comes up as ide. Also, a single number allows me to set the run level. When I first upgraded my kernel I *think* the cdrom native ide support was compiled into the kernel even though I did a "make oldconfig". Do a "make menuconfig" and make sure that cdrom native ide support is not compiled into your kernel.
The hdb=ide-scsi command is for the native ide cd-rom support if it's compiled into the kernel and shouldn't be ignored. With vanilla-sources and ck-sources the native ide cd-rom support skips hde, with gentoo-sources it doesn't. All three kernels have ide cd-rom support compiled into the kernel, not as a module. And with gentoo-sources the option ide2=ata66 doesn't work either. With the other two it works.
*** This bug has been marked as a duplicate of 17762 ***
