diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -4275,10 +4275,13 @@ */ old = atomic_load_int(&m->ref_count); do { + u_int count; + KASSERT(VPRC_WIRE_COUNT(old) > 0, ("vm_page_unwire: wire count underflow for page %p", m)); - if (old > VPRC_OBJREF + 1) { + count = old & ~VPRC_BLOCKED; + if (count > VPRC_OBJREF + 1) { /* * The page has at least one other wiring reference. An * earlier iteration of this loop may have called @@ -4287,7 +4290,7 @@ */ if ((vm_page_astate_load(m).flags & PGA_DEQUEUE) == 0) vm_page_aflag_set(m, PGA_DEQUEUE); - } else if (old == VPRC_OBJREF + 1) { + } else if (count == VPRC_OBJREF + 1) { /* * This is the last wiring. Clear PGA_DEQUEUE and * update the page's queue state to reflect the @@ -4296,7 +4299,7 @@ * clear leftover queue state. */ vm_page_release_toq(m, nqueue, noreuse); - } else if (old == 1) { + } else if (count == 1) { vm_page_aflag_clear(m, PGA_DEQUEUE); } } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1)); @@ -4572,6 +4575,8 @@ do { KASSERT(old != 0, ("vm_page_try_blocked_op: page %p has no references", m)); + KASSERT((old & VPRC_BLOCKED) == 0, + ("vm_page_try_blocked_op: page %p blocks wirings", m)); if (VPRC_WIRE_COUNT(old) != 0) return (false); } while (!atomic_fcmpset_int(&m->ref_count, &old, old | VPRC_BLOCKED));