Subject: Re: map user memory in kernel
To: Chuck Silvers <>
From: Emmanuel Dreyfus <>
List: tech-kern
Date: 11/06/2005 07:48:30
On Sat, Nov 05, 2005 at 06:52:56PM -0800, Chuck Silvers wrote:
> I don't see any robust way to construct a unique sleep address per futex
> with UVM.  for now, the best thing to do would be to use one global sleep
> address for all futex sleepers.

Yes, but how to cope with that:

process A maps some memory at address X
process B maps the same memory at address Y

A sleeps on futex at X, B wakes up futex at Y. That should wake up
process A. How do I discover (in kernel code) that X and Y are the same
VM object?

Emmanuel Dreyfus