os/doc
3
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity
doc/share/security/patches/EN-16:17/vm.patch

235 lines
6.2 KiB
Diff
Raw Blame History

--- sys/kern/vfs_subr.c.orig
+++ sys/kern/vfs_subr.c
@@ -2934,7 +2934,13 @@
TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) &&
vp->v_bufobj.bo_clean.bv_cnt == 0,
("vp %p bufobj not invalidated", vp));
- vp->v_bufobj.bo_flag |= BO_DEAD;
+
+ /*
+ * For VMIO bufobj, BO_DEAD is set in vm_object_terminate()
+ * after the object's page queue is flushed.
+ */
+ if (vp->v_bufobj.bo_object == NULL)
+ vp->v_bufobj.bo_flag |= BO_DEAD;
BO_UNLOCK(&vp->v_bufobj);
/*
--- sys/vm/vm_fault.c.orig
+++ sys/vm/vm_fault.c
@@ -286,7 +286,7 @@
vm_prot_t prot;
long ahead, behind;
int alloc_req, era, faultcount, nera, reqpage, result;
- boolean_t growstack, is_first_object_locked, wired;
+ boolean_t dead, growstack, is_first_object_locked, wired;
int map_generation;
vm_object_t next_object;
vm_page_t marray[VM_FAULT_READ_MAX];
@@ -423,11 +423,18 @@
fs.pindex = fs.first_pindex;
while (TRUE) {
/*
- * If the object is dead, we stop here
+ * If the object is marked for imminent termination,
+ * we retry here, since the collapse pass has raced
+ * with us. Otherwise, if we see terminally dead
+ * object, return fail.
*/
- if (fs.object->flags & OBJ_DEAD) {
+ if ((fs.object->flags & OBJ_DEAD) != 0) {
+ dead = fs.object->type == OBJT_DEAD;
unlock_and_deallocate(&fs);
- return (KERN_PROTECTION_FAILURE);
+ if (dead)
+ return (KERN_PROTECTION_FAILURE);
+ pause("vmf_de", 1);
+ goto RetryFault;
}
/*
--- sys/vm/vm_meter.c.orig
+++ sys/vm/vm_meter.c
@@ -93,30 +93,32 @@
CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_loadavg, "S,loadavg",
"Machine loadaverage history");
+/*
+ * This function aims to determine if the object is mapped,
+ * specifically, if it is referenced by a vm_map_entry. Because
+ * objects occasionally acquire transient references that do not
+ * represent a mapping, the method used here is inexact. However, it
+ * has very low overhead and is good enough for the advisory
+ * vm.vmtotal sysctl.
+ */
+static bool
+is_object_active(vm_object_t obj)
+{
+
+ return (obj->ref_count > obj->shadow_count);
+}
+
static int
vmtotal(SYSCTL_HANDLER_ARGS)
{
- struct proc *p;
struct vmtotal total;
- vm_map_entry_t entry;
vm_object_t object;
- vm_map_t map;
- int paging;
+ struct proc *p;
struct thread *td;
- struct vmspace *vm;
bzero(&total, sizeof(total));
+
/*
- * Mark all objects as inactive.
- */
- mtx_lock(&vm_object_list_mtx);
- TAILQ_FOREACH(object, &vm_object_list, object_list) {
- VM_OBJECT_WLOCK(object);
- vm_object_clear_flag(object, OBJ_ACTIVE);
- VM_OBJECT_WUNLOCK(object);
- }
- mtx_unlock(&vm_object_list_mtx);
- /*
* Calculate process statistics.
*/
sx_slock(&allproc_lock);
@@ -136,11 +138,15 @@
case TDS_INHIBITED:
if (TD_IS_SWAPPED(td))
total.t_sw++;
- else if (TD_IS_SLEEPING(td) &&
- td->td_priority <= PZERO)
- total.t_dw++;
- else
- total.t_sl++;
+ else if (TD_IS_SLEEPING(td)) {
+ if (td->td_priority <= PZERO)
+ total.t_dw++;
+ else
+ total.t_sl++;
+ if (td->td_wchan ==
+ &cnt.v_free_count)
+ total.t_pw++;
+ }
break;
case TDS_CAN_RUN:
@@ -158,29 +164,6 @@
}
}
PROC_UNLOCK(p);
- /*
- * Note active objects.
- */
- paging = 0;
- vm = vmspace_acquire_ref(p);
- if (vm == NULL)
- continue;
- map = &vm->vm_map;
- vm_map_lock_read(map);
- for (entry = map->header.next;
- entry != &map->header; entry = entry->next) {
- if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) ||
- (object = entry->object.vm_object) == NULL)
- continue;
- VM_OBJECT_WLOCK(object);
- vm_object_set_flag(object, OBJ_ACTIVE);
- paging |= object->paging_in_progress;
- VM_OBJECT_WUNLOCK(object);
- }
- vm_map_unlock_read(map);
- vmspace_free(vm);
- if (paging)
- total.t_pw++;
}
sx_sunlock(&allproc_lock);
/*
@@ -206,9 +189,18 @@
*/
continue;
}
+ if (object->ref_count == 1 &&
+ (object->flags & OBJ_NOSPLIT) != 0) {
+ /*
+ * Also skip otherwise unreferenced swap
+ * objects backing tmpfs vnodes, and POSIX or
+ * SysV shared memory.
+ */
+ continue;
+ }
total.t_vm += object->size;
total.t_rm += object->resident_page_count;
- if (object->flags & OBJ_ACTIVE) {
+ if (is_object_active(object)) {
total.t_avm += object->size;
total.t_arm += object->resident_page_count;
}
@@ -216,7 +208,7 @@
/* shared object */
total.t_vmshr += object->size;
total.t_rmshr += object->resident_page_count;
- if (object->flags & OBJ_ACTIVE) {
+ if (is_object_active(object)) {
total.t_avmshr += object->size;
total.t_armshr += object->resident_page_count;
}
--- sys/vm/vm_object.c.orig
+++ sys/vm/vm_object.c
@@ -737,6 +737,10 @@
vinvalbuf(vp, V_SAVE, 0, 0);
+ BO_LOCK(&vp->v_bufobj);
+ vp->v_bufobj.bo_flag |= BO_DEAD;
+ BO_UNLOCK(&vp->v_bufobj);
+
VM_OBJECT_WLOCK(object);
}
@@ -1722,6 +1726,9 @@
* case.
*/
if (backing_object->ref_count == 1) {
+ vm_object_pip_add(object, 1);
+ vm_object_pip_add(backing_object, 1);
+
/*
* If there is exactly one reference to the backing
* object, we can collapse it into the parent.
@@ -1793,11 +1800,13 @@
KASSERT(backing_object->ref_count == 1, (
"backing_object %p was somehow re-referenced during collapse!",
backing_object));
+ vm_object_pip_wakeup(backing_object);
backing_object->type = OBJT_DEAD;
backing_object->ref_count = 0;
VM_OBJECT_WUNLOCK(backing_object);
vm_object_destroy(backing_object);
+ vm_object_pip_wakeup(object);
object_collapses++;
} else {
vm_object_t new_backing_object;
@@ -2130,6 +2139,7 @@
*/
if (!reserved && !swap_reserve_by_cred(ptoa(next_size),
prev_object->cred)) {
+ VM_OBJECT_WUNLOCK(prev_object);
return (FALSE);
}
prev_object->charge += ptoa(next_size);
--- sys/vm/vm_object.h.orig
+++ sys/vm/vm_object.h
@@ -181,7 +181,6 @@
*/
#define OBJ_FICTITIOUS 0x0001 /* (c) contains fictitious pages */
#define OBJ_UNMANAGED 0x0002 /* (c) contains unmanaged pages */
-#define OBJ_ACTIVE 0x0004 /* active objects */
#define OBJ_DEAD 0x0008 /* dead objects (during rundown) */
#define OBJ_NOSPLIT 0x0010 /* dont split this object */
#define OBJ_PIPWNT 0x0040 /* paging in progress wanted */
Reference in a new issue View git blame Copy permalink