vs_alloc can underflow in L2ARC vdevs

[mirror_zfs.git] / module / zfs / vdev.c

diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c
index 50d230ccb240be1bd06ffe70aec15541e8062914..def98ad136f10a2e4c6949db85ae056c4036f2ed 100644 (file)
--- a/module/zfs/vdev.c
+++ b/module/zfs/vdev.c
@@ -4162,6 +4162,11 @@ vdev_space_update(vdev_t *vd, int64_t alloc_delta, int64_t defer_delta,
        dspace_delta = vdev_deflated_space(vd, space_delta);
 
        mutex_enter(&vd->vdev_stat_lock);
+       /* ensure we won't underflow */
+       if (alloc_delta < 0) {
+               ASSERT3U(vd->vdev_stat.vs_alloc, >=, -alloc_delta);
+       }
+
        vd->vdev_stat.vs_alloc += alloc_delta;
        vd->vdev_stat.vs_space += space_delta;
        vd->vdev_stat.vs_dspace += dspace_delta;
@@ -4169,6 +4174,7 @@ vdev_space_update(vdev_t *vd, int64_t alloc_delta, int64_t defer_delta,
 
        /* every class but log contributes to root space stats */
        if (vd->vdev_mg != NULL && !vd->vdev_islog) {
+               ASSERT(!vd->vdev_isl2cache);
                mutex_enter(&rvd->vdev_stat_lock);
                rvd->vdev_stat.vs_alloc += alloc_delta;
                rvd->vdev_stat.vs_space += space_delta;