Description of Problem: When i try to mount the cdrom, the system hangs and requires a hard reboot Version-Release number of selected component (if applicable): red hat linux v 7.2 How Reproducible: Steps to Reproduce: 1. 2. 3. Actual Results: Expected Results: Additional Information:
I have installed redhat liux 7.2 under intel where i am facing the problem of system freezing when trying to mount the cdrom (iso ). I have also installed redhat linxu 7.1 under amd which isworking proper
do you have any idea which model cdrom you're using ? (if not, typing cat /proc/ide/*/model as root will tell me which it is)
I have come across the same problem on: 1, linux 7.2 2, An AMD k63 3, CD re-write drive, a Goldstar/LG, GCE-8160B., ide channel 1, set as master with a slave SYQUEST drive. When I try to mount a disk for read, the read light flashes for about 30 seconds and then a re-boot is required. The same thing happens if I do a dd if=/dev/crdrom etc. The cd-rom was set up to be used for re burning with cdrecord, i.e. ide-scsi was loaded. I have now removed the ide-scsi and access the CD-rom directly on hdc and I can now use the cd-rom for read only, which is only OK for the short term. I saw that round about release 2.4.10 of the kernel, a bug was fixed for scsi buffer race condition, any comment on that patch as a possible fix?
This will only help if you are using the SCSI emulation. You can tell by see which real device /dev/cdrom is linked to, if it is linked to something like /dev/sc0, then you have scsi emulation. To get the full picture, see /usr/share/doc/howto/CDROM-howto, if you have that installed. The way I disabled ide-scsi is as follow: I am using grub as the boot loader. I have a boot file system called /boot go into /boot/grub/grub.conf and remove the words "hdc=ide-scsi", your cd-rom may not be hdc, you will need to sort that. Then re-boot. Don't forget to save a copy of your old config file in case everything goes pear shape. Hope that works for you, best of luck. Regards
My final comment on this one: In my case, the problem was caused by the the fact that when using the ide-sccsi driver, the mode of access default to DMA. Once I have disabled dma access, every thing now works. I have to disable DMA by changing /etc/rc.d/ec.local, I added the line: hdparm -d0 /dev/hdc Regards