From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nivedita Singhvi <niv@us.ibm.com>
Subject: Re: Changing semantics of ioperm() on Xen x86-64?
Date: Tue, 18 Apr 2006 16:36:20 -0700
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To: Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk>
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Ian Pratt wrote:
>>As part of the Xen x86-64 Linux port, we've changed the 
>>ioperm() syscall to always modify the IOPL instead of 
>>actually modifying the IO bitmap in the TSS like we do on 
>>x86-32.  Is there a particular reason for doing this?
> 
> 
> I don't believe so. io bitmap support was added to the hypervisor and
> the corresponding ioperm support got added on i386, but was never
> carried across to x86_64.
> 
> We would definitely benefit from someone doing a code review of x86_64
> with a view to unifying as many of the xen patches with i386 as
> possible. There's certainly some needless/unhelpful divergence.
> 
> Ian 

Above issue was caught by a LTP test case failure, btw...

thanks,
Nivedita