Hello, I've often seen gnumach deadlocking in this situation:
lock_write (kern/lock.c:284). kmem_alloc_wired(zone_map) (vm/vm_kern.c:537). zget_space (kern/zalloc.c:316). zalloc (kern/zalloc.c:508). _vm_map_entry_create (vm/vm_map.c:262). _vm_map_clip_end (vm/vm_map.c:1094). vm_map_delete (vm/vm_map.c:1704). vm_map_remove (vm/vm_map.c:1757). kmem_free(zone_map) (vm/vm_kern.c:699). consider_zone_gc (kern/zalloc.c:826). vm_pageout_scan (vm/vm_pageout.c:559). vm_pageout_continue (vm/vm_pageout.c:903). The problem here is that kmem_free(zone_map) leads to a call to vm_ma_delete which locks zone_map and leads to a zalloc call (for the new entry because of splitting), which needs to call zget_space and thus kmem_alloc_wired(zone_map), which _also_ tries to lock zone_map... Unfortunately we can not afford to just avoid the second lock, as it may completely thrash what vm_map_delete is doing... Samuel
