system hang if iopl called before getting pci access structure

From: Jitesh K Patil, Systems Engineer, Wipro Technologies. (jitesh.kpatil_at_wipro.com)
Date: 08/20/03 

Date: 19 Aug 2003 21:36:20 -0700

Hi All,
I am trying to read a pci device.
Here is the snippet of the code with the problem in comments...

=============================================================
// Platform..... IA64
// OS........... Redhat Linux Advanced Server 2.1
// Kernel....... 2.4.18
// Build Tool... gcc
// Build Cmd.... gcc -O0 Try.c -lpci

// Get access structure
acc = pci_alloc() ;
pci_init(acc) ;
pci_scan_bus(acc);

// give permissions
// When I tried calling iopl(1) prior to the three lines of code above,
// the system hung, and I had to do a hard reset of the system.
// Why would this happen?
iopl(1) ;

// Get Device structure pointer
dev = pci_get_dev(acc, BUS, DEV, FNC);
=============================================================

Thanx in advance,
Jitesh

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