SCSI DVD ROM vanishes after kernel recompilation
 

Hi all. A have a Dell PowerEdge r410 Xeon Quad E5506 running with CentOS 5.3

The kernel from distro is a 2.6.18. Everything goes fine with the initial installation, but strange things starts to happen once i recompile the kernel for the 2.6.23 version, since my DVD rom just vanishes from the system. Here is the content for /proc/scsi/scsi:

Before the compilation (kernel v 2.6.18):
Host: scsi0 Channel: 00 Id: 32 Lun: 00
Vendor: DP Model: BACKPLANE Rev: 1.07
Type: Enclosure ANSI SCSI revision: 05
Host: scsi0 Channel: 02 Id: 00 Lun: 00
Vendor: DELL Model: PERC 6/i Adapter Rev: 1.22
Type: Direct-Access ANSI SCSI revision: 05
Host: scsi3 Channel: 00 Id: 00 Lun: 00
Vendor: TSSTcorp Model: DVD-ROM TS-L333A Rev: D350
Type: CD-ROM ANSI SCSI revision: 05


After the compilation (kernel v 2.6.23)

Host: scsi0 Channel: 00 Id: 32 Lun: 00
Vendor: DP Model: BACKPLANE Rev: 1.07
Type: Enclosure ANSI SCSI revision: 05
Host: scsi0 Channel: 02 Id: 00 Lun: 00
Vendor: DELL Model: PERC 6/i Adapter Rev: 1.22
Type: Direct-Access ANSI SCSI revision: 05

I didnt change a thing about the scsi drivers on the kernel configuration. Anyone have a clue?

Hmmm, for some reason I misread your problem as being with SATA, not with SCSI. I suspect that it's in the same type of thing, though, since it happened around 2.6.18, so I'm leaving my original post here. Make sure that CONFIG_SCSI hasn't been removed from your .config file.


Original:
They made a pretty serious change after 2.6.18 that affects only /dev/sdx devices. Look in your .config file and change all occurrences of "CONFIG_SCSI_SATA" to "CONFIG_SATA". Do not change "CONFIG_SCSI" as that is a valid name.

Or, you can do it this way and then recompile/reinstall:
http://www.linuxquestions.org/questi...7/#post3540344

firsten

I suspect I know the answer but what distro and version are you running?

Edit: Missed it.


If you are trying to build a vanilla kernel for RHEL/Centos you are in for a real battle. RHEL/Centos patches the kernels to be the equivalent (roughly) of a current kernel. 2.6.18-128.4.1.el5 is probably much closer to a .26 vanilla kernel than it is to a .18 vanilla kernel. The rest of the entire system relies that those patches will be there. If you are trying to build the kernel for security reasons, save your time becuase they are very probably already patched in. If you are trying to add hardware support first make sure that -128 does not have it, it has more hardware support than a vanilla .23 kernel. If you really must rebuild the kernel grab the src rpm(for the most current RHEL kernel). It will contain spec file and all the patches.

Thanks for the advise, will do that! The thing is i need to recompile the kernel because i work with some real time programming with RTAI, and in order to do that, need to patch and rebuild the kernel with the vanilla 2.6.23 version. The RTAI is working fine so far, but the cdrom just vanished and i will need it for future use. Ill give an update as soon as possible.