Allocations in the various pmap_enter(9) are done with uvm_pagealloc(9),
which sets the UVM_PLA_NOWAIT flag, and/or with pool_get(9) w/ PR_NOWAIT.
So the comment below seems outdated to me, ok to kill it?
Index: uvm/uvm_fault.c
===================================================================
RCS file: /cvs/src/sys/uvm/uvm_fault.c,v
retrieving revision 1.98
diff -u -p -r1.98 uvm_fault.c
--- uvm/uvm_fault.c 12 Sep 2020 17:08:49 -0000 1.98
+++ uvm/uvm_fault.c 22 Sep 2020 07:46:43 -0000
@@ -702,13 +702,6 @@ ReFault:
pmap_update(ufi.orig_map->pmap);
/* (shadowed == TRUE) if there is an anon at the faulting address */
- /*
- * note that if we are really short of RAM we could sleep in the above
- * call to pmap_enter. bad?
- *
- * XXX Actually, that is bad; pmap_enter() should just fail in that
- * XXX case. --thorpej
- */
/*
* if the desired page is not shadowed by the amap and we have a
* backing object, then we check to see if the backing object would
