On Thursday 16 December 2004 22:51, Manuel Bouyer wrote:
> OK, thanks. Well, this won't work for xen, where disabling/enabling
> interrupts is done by writing a memory shared with the hyperviror.
> Does read_psl()/write_psl() do something else than just cli/sti here ?
> Could this be changed to cli()/sti() (which are macro doing the right
> thing on port-xen) ?

It seems clear that the intent was to restore the old value of the interrupt 
flag.  I have no idea why it was done this way -- the old code (written by 
me) didn't do that; it used cli/sti in Xspllower() for all the 
synchronization it needed, and interrupts were *always* enabled on entry.