On Mar 12, 2005, at 6:04 PM, Izumi Tsutsui wrote:

> In article <fef370f6c0bb24a670f6671e36176417@shagadelic.org>
> thorpej@shagadelic.org wrote:
>
>> Unfortunately, it is very difficult to enforce at what VA a PA will be
>> mapped, and very hard to be that selective about PA if a VA has 
>> already
>> been selected.  Consider two different programs that map libc at
>> different addresses.
>
> Then, how can we avoid/handle virtual aliases (especially for userland)
> on R4600/R5000 machines for now? On my quick tests, all dynamic linked
> binaries cause VCED on R4400 newsmips.

I have felt for a long time, that when mmap chooses a dynamic address 
for a
vnode, it should use an existing mapped adress for that vnode, or 
choose a
new address that has no other vnode mapped as text.  This would 
magically
eliminate a lot of virtual aliases.

Keeping track of such mapping I don't think would be that difficult.

-- 
Matt Thomas                     email: matt@3am-software.com
3am Software Foundry              www: http://3am-software.com/bio/matt/
Cupertino, CA              disclaimer: I avow all knowledge of this 
message.