Bug 83949

Summary: CD-RW kernel panic mount cdrom
Product: [Retired] Red Hat Linux Reporter: epicmyth <brian>
Component: kernelAssignee: Arjan van de Ven <arjanv>
Status: CLOSED WORKSFORME QA Contact: Brian Brock <bbrock>
Severity: low Docs Contact:
Priority: low    
Version: 8.0   
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2003-02-10 15:30:07 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description epicmyth 2003-02-10 13:28:55 UTC
From Bugzilla Helper:
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Description of problem:
OS: Red Hat 8.0 (Psyche)
Plat: i386 (Dell 866 512 SDRAM  pent III)

Install goes smoothly (CD install), however, after the install mounting the
CDROM /mnt/cdrom causes a kernel panic.  This can be anywhere from right after
the CD install on the last page (where you can install additional components),
to actually working within the OS via GNOME/KDE etc etc. 

This has happend on both the "out of box" and updated versions of the kernel.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1.Install Red Hat 8.0 from CDROM
2.log into GNOME/KDE/failsafe/Windowmaker/fvwm
3.mount /mnt/cdrom


Actual Results:  Kenrel Panic (IE: complete freeze, keyboard lights blink)

Expected Results:  the CD should have mounted for readability

Additional info:

Comment 1 epicmyth 2003-02-10 15:30:07 UTC
Bug Solution: Turning off DMA or disabling it at bootup (as a workaround).
Device Spacifics:

scsi0 : SCSI host adapter emulation for IDE ATAPI devices
Vendor: LG        Model: CD-RW CED-8080B   Rev: 1.04
Type:   CD-ROM                             ANSI SCSI revision: 02


To check if DMA is on/off: (as root at console) /sbin/hdparm -d /dev/hdc 
To turn DMA off once shown it is on: (as root at console) /sbin/hdparm -d0 /dev/hdc

If this works, then cd /etc and edit rc.local with this line: /sbin/hdparm -d0
/dev/hdc to turn off DMA at bootup. 

Thanks to |Jef| for the solution =D