uvm_km_alloc(9) has never been used in amd64's pmap. pool_get(9) is the thing since its import by mickey@.
ok? Index: arch/amd64/amd64/pmap.c =================================================================== RCS file: /cvs/src/sys/arch/amd64/amd64/pmap.c,v retrieving revision 1.135 diff -u -p -r1.135 pmap.c --- arch/amd64/amd64/pmap.c 20 Sep 2019 09:38:22 -0000 1.135 +++ arch/amd64/amd64/pmap.c 2 Nov 2019 12:00:41 -0000 @@ -180,15 +180,11 @@ * * [A] new process' page directory page (PDP) * - plan 1: done at pmap_create() we use - * uvm_km_alloc(kernel_map, PAGE_SIZE) [fka kmem_alloc] to do this - * allocation. + * pool_get(&pmap_pmap_pool, PR_WAITOK) to do this allocation. * * if we are low in free physical memory then we sleep in - * uvm_km_alloc -- in this case this is ok since we are creating + * pool_get() -- in this case this is ok since we are creating * a new pmap and should not be holding any locks. - * - * if the kernel is totally out of virtual space - * (i.e. uvm_km_alloc returns NULL), then we panic. * * XXX: the fork code currently has no way to return an "out of * memory, try again" error code since uvm_fork [fka vm_fork]
