Tyan k8sr lockups

Gary Mu1der gmulder at infotechfl.com
Mon Apr 4 08:43:09 PDT 2005

I had suspected that, but I've done the same on a P4 system with 5.3REL, 
Solaris on Sparc (although I don't know if Sparc has memory mapped I/O), 
and other Unixes, and had no problems.

It was a quick a dirty way to stress the memory and CPU.

Thanks for the reply,

Doug White wrote:
> On Fri, 1 Apr 2005, Gary Mu1der wrote:
>>I have isolated the crash to the following dd command:
>>	dd if=/dev/mem of=/dev/null bs=1024k skip=4040 count=1
> Reading from random places in /dev/mem will cause unpredicatable behavior.
> Memory at that offset is in PCI memory-mapped device space, and reading
> from there may disrupt the PCI bridge, enable or disable interrupts, or
> worse.

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