Comment 0 for bug 307829

I've had some trouble with DVD playback on Intrepid; I had the same problems with custom-compiled 2.6.25, 2.6.26 and 2.6.27 kernels on Hardy as well, so something apparently changed in 2.6.25 that affected my DVD drive. I've narrowed it down somewhat - apparently the pata_amd module is setting my DVD drive to PIO0 mode, which makes my DVD playback jerky and slows down my entire system when doing anything DVD-related. Partial output from "dmesg | grep ata" is how I discovered this:

[ 3.477302] libata version 3.00 loaded.
[ 4.000348] pata_amd 0000:00:0d.0: version 0.3.10
[ 4.000410] pata_amd 0000:00:0d.0: setting latency timer to 64
[ 4.000567] scsi0 : pata_amd
[ 4.000714] scsi1 : pata_amd
[ 4.001674] ata1: PATA max UDMA/133 cmd 0x1f0 ctl 0x3f6 bmdma 0x3080 irq 14
[ 4.001678] ata2: PATA max UDMA/133 cmd 0x170 ctl 0x376 bmdma 0x3088 irq 15
[ 4.328473] ata2.00: ATAPI: MATSHITAUJ-840D, 1.02, max MWDMA2
[ 4.328490] ata2: nv_mode_filter: 0x39f&0x7001->0x1, BIOS=0x0 (0x0) ACPI=0x7001 (60:600:0x11)
[ 4.345511] ata2.00: configured for PIO0

I tried blacklisting pata_amd, but it didn't seem to work. How do I disable it or prevent it from setting my drive to PIO mode, and why is it doing this in the first place?