Description of problem: After upgraded to kernel-2.6.19-1.2895.fc6, I can no longer access the hard disks on my Adaptec 2100S Raid adapter. /var/log/messages shows: Feb 4 21:46:09 xxx kernel: I2O subsystem v1.325 Feb 4 21:46:09 xxx kernel: i2o: max drivers = 8 Feb 4 21:46:09 xxx kernel: i2o: Checking for PCI I2O controllers... Feb 4 21:46:09 xxx kernel: ACPI: PCI Interrupt 0000:00:09.1[A] -> GSI 18 (level, low) -> IRQ 16 Feb 4 21:46:09 xxx kernel: iop0: controller found (0000:00:09.1) Feb 4 21:46:09 xxx kernel: iop0: PCI I2O controller at D6000000 size=1048576 Feb 4 21:46:09 xxx kernel: iop0: Installed at IRQ 16 Feb 4 21:46:10 xxx kernel: i2o: iop0: Activating I2O controller... Feb 4 21:46:10 xxx kernel: i2o: iop0: This may take a few minutes if there are many devices Feb 4 21:46:10 xxx kernel: iop0: HRT has 1 entries of 16 bytes each. Feb 4 21:46:10 xxx kernel: Adapter 00000012: TID 0000:[HPC*]:PCI 1: Bus 1 Device 22 Function 0 Feb 4 21:46:10 xxx kernel: i2o: iop0: Controller added Feb 4 21:46:10 xxx kernel: I2O Block Device OSM v1.325 Feb 4 21:46:10 xxx kernel: block-osm: registered device at major 80 Feb 4 21:46:10 xxx kernel: i2o/hda:<3>Buffer I/O error on device i2o/hda, logical block 0 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 0 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 0 Feb 4 21:46:10 xxx kernel: unable to read partition table Feb 4 21:46:10 xxx kernel: block-osm: device added (TID: 202): i2o/hda Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 8978928 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 8978928 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 0 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 1 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 2 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 3 Feb 4 21:46:10 xxx kernel: Buffer I/O error on device i2o/hda, logical block 4 /dev/i2o/hda* works ok after I reverted back to kernel-2.6.18-1.2869.fc6. Version-Release number of selected component (if applicable): kernel-2.6.19-1.2895.fc6 How reproducible: Always.