I'll be very gratefull, if you help me solving a CD-RW problem.
My preliminary remark is my CD/DVD devices read rigth both CD-RW and DVD-ROM.
Essential data are these:

Linux version 2.6.5-gentoo-r1

gcc version 3.3.2 20031218
************************************************** *********************************

dmesg excerpt:

Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
ICH4: IDE controller at PCI slot 0000:00:1f.1
ICH4: chipset revision 2
ICH4: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hdaMA, hdbMA
ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdcMA, hddio
hda: Maxtor 6Y080L0, ATA DISK drive
hdb: HL-DT-STDVD-ROM GDR8161B, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hdc: HL-DT-ST GCE-8520B, ATAPI CD/DVD-ROM drive
ide1 at 0x170-0x177,0x376 on irq 15
hda: max request size: 128KiB
hda: 160086528 sectors (81964 MB) w/2048KiB Cache, CHS=65535/16/63, UDMA(100)
/dev/ide/host0/bus0/target0/lun0: p1 p2 < p5 p6 p7 p8 p9 > p3 p4
hdb: ATAPI 48X DVD-ROM drive, 256kB Cache, UDMA(33)
Uniform CD-ROM driver Revision: 3.20
hdc: ATAPI 40X CD-ROM CD-R/RW CD-MRW drive, 2048kB Cache, UDMA(33)


This's not right;my CD-ROM is 52x24x52x.
My DVD-ROM is reading compatible 16x/48x, and it's not a problem.

************************************************** **********************************

Command:

#hdparm -tT /dev/hdc

/dev/hdc:
Timing buffer-cache reads: 1304 MB in 2.00 seconds = 650.47 MB/sec
Timing buffered disk reads: 8 MB in 3.15 seconds = 2.54 MB/sec


This's not right; 2.54 MB/sec is equivalent to 17x.

************************************************** *********************************
Mastering command:

#cdrecord dev=ATAPI:1,0,0 file.img

Scanning command:

#dd if=/dev/hdc of=/dev/null

dd: reading `/dev/hdc': Input/output error
70784+0 records in
70784+0 records out

In the scanning dmesg :

#dmesg
..
..
..
..
..
Buffer I/O error on device hdc, logical block 8851
hdc: command error: status=0x51 { DriveReady SeekComplete Error }
hdc: command error: error=0x54
end_request: I/O error, dev hdc, sector 70816

************************************************** *********************************
I add this:

1) With WindowsXP my CD-RW is right.
2) I'd same errors mastering on FreeBsd 5.2.1, 4.8.
3) I'd same errors mastering on RedHat9, Fedora, Suse whit 2.4 kernels.
4) My kernel is monolithic (except nvidia, my only module).
5) CONFIG_IDEDISK_MULTI_MODE=yes.