On Fri, Feb 21, 2020 at 02:06:26PM +0100, Paolo Bonzini wrote:
> On 21/02/20 13:59, Stefan Hajnoczi wrote:
> > 1. It doesn't crash if the node is currently not on a list.
> > 2. It clears the node's linked list pointers so that future linked
> >    list operations (like QLIST_SAFE_REMOVE()) aren't accidentally
> >    performed on stale pointers.
> >
> > The node has a long lifespan and will be inserted into ready_lists
> > multiple times.  We need to safely remove it from ready_list to protect
> > against a corruption the next time the node is inserted into a
> > ready_list again:
> 
> Ah, so the one I singled out is for (2) (we know the node is currently
> on a list), while the one below is for (1).  Would it make sense to move
> (2) to Q*_REMOVE_*?  We can do it separately after this pull request.

Extending all Q*_REMOVE*() macros to clear the linked list pointers is
nice.  I'll send a follow-up patch.

Stefan