> The UTCB is a central information page for L4 userspace threads > and it's pretty difficult to find another x86 register that can > be used to point to it.
What's wrong with %fs? But anyway, that is fine if the one word at %gs:0 can be made available for user use. Ideally that word would be writable (which you could manage along with read-only use by situating the segment base on a page boundary, one page writable and one not). But the only thing that would write it is pthreads innards, so it would be workable to have a system call to set the %gs:0 word for a thread. I don't know the L4 interfaces, but why not just make this page accessible at a canonical address accessible from the standard user %ds segment? _______________________________________________ Bug-hurd mailing list [EMAIL PROTECTED] http://mail.gnu.org/mailman/listinfo/bug-hurd
