Red Hat Bugzilla – Bug 112917
Total system lockup writing to floppy disk
Last modified: 2007-11-30 17:10:35 EST
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Description of problem:
I am seeing solid lockups whenever the system writes more than a
tiny amount of data to the floppy drive (1.44MB HD, /dev/fd0H1440).
My system is an Intel Celeron 2400 MHz on an Asus P4S800 motherboard
(SiS 648FX, SiS 963L chipset). I've upgraded to
kernel-2.4.22-1.2135.nptl.i686 and the behavior persists. What I find
odd is that a Mandrake 9.2 installation with a kernel also based on
2.4.22 does not have this problem. With Fedora, I can _read_ floppies
just fine (reading from the raw device, or a file system mounted
read-only), but an attempt to write always fails.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Run: dd if=/dev/zero of=/dev/fd0H1440
Actual Results: System locks up totally. Reset or power-cycle required.
Expected Results: No lockup.
Bug #111762 appears to be this same problem on a different platform
Building a customized kernel tailored to my system appears to have
made the problem go away. I made a lot of configuration changes, but
if I can identify a particular change that seems to be responsible,
I'll add another comment with that info.
The offending parameter is CONFIG_APM_CPU_IDLE. If I disable that
feature, the floppy drive works perfectly. With that feature enabled,
writing to the floppy locks up the system every time. In all the
supplied Fedora kernel configurations, CONFIG_APM_CPU_IDLE is enabled.
In the Mandrake kernel it is disabled.
thankfully CPU_IDLE can be turned off with a commandline option...
Also can you attach the output from dmidecode to this bug? With that
we can blacklist your bios for apmidle so that it will JustWork(tm) in
Created attachment 96797 [details]
Output from dmidecode
For the benefit of anyone who discovers this bug report while
searching for a solution, here are the relevant kernel boot parameters
that will prevent the lockups (for me, anyway):
To eliminate APM entirely:
OR, to stop just the CPU_IDLE BIOS calls:
Thanks for the bug report. However, Red Hat no longer maintains this version of
the product. Please upgrade to the latest version and open a new bug if the problem
The Fedora Legacy project (http://fedoralegacy.org/) maintains some older releases,
and if you believe this bug is interesting to them, please report the problem in
the bug tracker at: http://bugzilla.fedora.us/