the uvm_km_pgremove_intrsafe function requires pages to be mapped to free them however it is then expected to call pmap_kremove(). This is scary as in the page is freed, but is still mapped.
Have uvm_km_pgremove_intrsafe() unmap as well as free. Index: uvm/uvm_glue.c =================================================================== RCS file: /cvs/src/sys/uvm/uvm_glue.c,v retrieving revision 1.56 diff -u -p -r1.56 uvm_glue.c --- uvm/uvm_glue.c 1 Apr 2011 15:43:13 -0000 1.56 +++ uvm/uvm_glue.c 1 Apr 2011 18:08:52 -0000 @@ -260,7 +260,6 @@ uvm_vslock_device(struct proc *p, void * return 0; uvm_km_pgremove_intrsafe(sva, sva + sz); - pmap_kremove(sva, sz); pmap_update(pmap_kernel()); out_unmap: uvm_km_free(kernel_map, sva, sz); @@ -291,7 +290,6 @@ uvm_vsunlock_device(struct proc *p, void kva = trunc_page((vaddr_t)map); uvm_km_pgremove_intrsafe(kva, kva + sz); - pmap_kremove(kva, sz); pmap_update(pmap_kernel()); uvm_km_free(kernel_map, kva, sz); } Index: uvm/uvm_km.c =================================================================== RCS file: /cvs/src/sys/uvm/uvm_km.c,v retrieving revision 1.86 diff -u -p -r1.86 uvm_km.c --- uvm/uvm_km.c 26 Aug 2010 16:08:24 -0000 1.86 +++ uvm/uvm_km.c 1 Apr 2011 18:25:51 -0000 @@ -326,6 +326,7 @@ uvm_km_pgremove_intrsafe(vaddr_t start, pg = PHYS_TO_VM_PAGE(pa); if (pg == NULL) panic("uvm_km_pgremove_intrsafe: no page"); + pmap_kremove(va, PAGE_SIZE); uvm_pagefree(pg); } } Index: uvm/uvm_map.c =================================================================== RCS file: /cvs/src/sys/uvm/uvm_map.c,v retrieving revision 1.131 diff -u -p -r1.131 uvm_map.c --- uvm/uvm_map.c 24 Dec 2010 21:49:04 -0000 1.131 +++ uvm/uvm_map.c 1 Apr 2011 18:11:38 -0000 @@ -1639,7 +1639,6 @@ uvm_unmap_remove(struct vm_map *map, vad } } else if (map->flags & VM_MAP_INTRSAFE) { uvm_km_pgremove_intrsafe(entry->start, entry->end); - pmap_kremove(entry->start, len); } else if (UVM_ET_ISOBJ(entry) && UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { KASSERT(vm_map_pmap(map) == pmap_kernel()); Dale Rahn dr...@dalerahn.com