Description of problem: In short, DMA is not enabled on my laptop's DVD drive. The kernel explicitly disables it on bootup, and as a result the whole system is jerky when the drive is in use. Version-Release number of selected component (if applicable): Fedora 9, x86_64, kernel 2.6.25.3-18.fc9.x86_64. Running on an Acer Ferrari 4000 laptop, ATI 200M chipset, using the pata_atiixp driver. (Drive is PATA, not SATA) dmesg attached, but here is the relevant bit: ACPI: PCI Interrupt 0000:00:14.1[A] -> GSI 16 (level, low) -> IRQ 16 scsi0 : pata_atiixp scsi1 : pata_atiixp ata1: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0x8410 irq 14 ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0x8418 irq 15 ata1.00: ATA-6: TOSHIBA MK1032GAX, AB211A, max UDMA/100 ata1.00: 195371568 sectors, multi 16: LBA48 ata1.00: configured for UDMA/100 ata2.00: ATAPI: MATSHITADVD-RAM UJ-845S, D200, max UDMA/33 ata2.00: simplex DMA is claimed by other device, disabling DMA ata2.00: configured for PIO4 The problem seems to be the same as these: http://www.mail-archive.com/linux-ide@vger.kernel.org/msg04494.html https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/175022 If I could force-enable this somehow that would be fine, but the fact that it starts up wrong is a problem.
Created attachment 308500 [details] dmesg with the problem.
*** This bug has been marked as a duplicate of 450191 ***