Hi, I have several desktop machines and notebooks which have CDROM / DVDROM connected to IDE SATA interfaces and they all have DMA disabled. Every time the CDROM/DVDROM drives are accessed, the computers slow down a lot and become almost unusable till it's finished. hdparm shows: [marcelo.sales@sf002698 ~]$ /sbin/hdparm /dev/dvd /dev/dvd: IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 0 (off) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) HDIO_GETGEO failed: Inappropriate ioctl for device When I try to enable DMA using hdparm, I get: [root@sf002698 ~]# hdparm -d1 /dev/dvd /dev/dvd: setting using_dma to 1 (on) HDIO_SET_DMA failed: Operation not permitted using_dma = 0 (off) Checking the config file for the stock kernel installed in these machines, I see: [marcelo.sales@sf002698 ~]$ grep _BLK_ /boot/config-$(uname -r) | grep SATA # CONFIG_BLK_DEV_IDE_SATA is not set I assume this is the reason why I can't turn on DMA, am I right? I believe many, many people shall suffer from this problem too. Should I open an RFE asking to enable this in the next kernel or is there a specific reason for not enabling this in the stock kernels? I hope I'll not need to recompile the kernel and install it in all these machines just because of this :) Thanks, Marcelo
