From: Martin Pieuchot <mpi@grenadille.net>
Subject: Update assertions in pgo_get()
To: tech@openbsd.org
Date: Wed, 18 Dec 2024 17:48:56 +0100

The two pgo_get() implementations no longer modify pages when PGO_LOCKED
is passed.  They are ready to be called with a shared lock, so update the
assertions to reflect that.

ok?

diff --git sys/uvm/uvm_aobj.c sys/uvm/uvm_aobj.c
index 8176f22a6a4..e8a97454a42 100644
--- sys/uvm/uvm_aobj.c
+++ sys/uvm/uvm_aobj.c
@@ -999,7 +999,9 @@ uao_get(struct uvm_object *uobj, voff_t offset, struct vm_page **pps,
 	boolean_t done;
 
 	KASSERT(UVM_OBJ_IS_AOBJ(uobj));
-	KASSERT(rw_write_held(uobj->vmobjlock));
+	KASSERT(rw_lock_held(uobj->vmobjlock));
+	KASSERT(rw_write_held(uobj->vmobjlock) ||
+	    ((flags & PGO_LOCKED) != 0 && (access_type & PROT_WRITE) == 0));
 
 	/*
  	 * get number of pages
diff --git sys/uvm/uvm_vnode.c sys/uvm/uvm_vnode.c
index d9fc19f6dcb..17e3853b1a0 100644
--- sys/uvm/uvm_vnode.c
+++ sys/uvm/uvm_vnode.c
@@ -950,8 +950,9 @@ uvn_get(struct uvm_object *uobj, voff_t offset, struct vm_page **pps,
 	int lcv, result, gotpages;
 	boolean_t done;
 
-	KASSERT(((flags & PGO_LOCKED) != 0 && rw_lock_held(uobj->vmobjlock)) ||
-	    (flags & PGO_LOCKED) == 0);
+	KASSERT(rw_lock_held(uobj->vmobjlock));
+	KASSERT(rw_write_held(uobj->vmobjlock) ||
+	    ((flags & PGO_LOCKED) != 0 && (access_type & PROT_WRITE) == 0));
 
 	/* step 1: handled the case where fault data structures are locked. */
 	if (flags & PGO_LOCKED) {