From 11f2e9a491baa2ae3fc00f6b8b892fa91a852ca1 Mon Sep 17 00:00:00 2001 From: fbynite <52733326+fbynite@users.noreply.github.com> Date: Sat, 20 Feb 2021 19:19:20 -0900 Subject: [PATCH] vdev_ops: don't try to call vdev_op_hold or vdev_op_rele when NULL This prevents a panic after a SLOG add/removal on the root pool followed by a zpool scrub. When a SLOG is removed, a hole takes its place - the vdev_ops for a hole is vdev_hole_ops, which defines the handler functions of vdev_op_hold and vdev_op_rele as NULL. This bug has been reported in illumos and FreeBSD, a different trigger in the FreeBSD report though. Credit for this patch goes to Patrick Mooney Obtained from: illumos-gate commit: c65bd18728f34725 External-issue: https://www.illumos.org/issues/12981 External-issue: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=252396 Reviewed-by: Brian Behlendorf Signed-off-by: Rob Wing Closes #11623 --- module/zfs/vdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c index 64016311b9cf..ad4f3efb87b1 100644 --- a/module/zfs/vdev.c +++ b/module/zfs/vdev.c @@ -2527,7 +2527,7 @@ vdev_hold(vdev_t *vd) for (int c = 0; c < vd->vdev_children; c++) vdev_hold(vd->vdev_child[c]); - if (vd->vdev_ops->vdev_op_leaf) + if (vd->vdev_ops->vdev_op_leaf && vd->vdev_ops->vdev_op_hold != NULL) vd->vdev_ops->vdev_op_hold(vd); } @@ -2538,7 +2538,7 @@ vdev_rele(vdev_t *vd) for (int c = 0; c < vd->vdev_children; c++) vdev_rele(vd->vdev_child[c]); - if (vd->vdev_ops->vdev_op_leaf) + if (vd->vdev_ops->vdev_op_leaf && vd->vdev_ops->vdev_op_rele != NULL) vd->vdev_ops->vdev_op_rele(vd); }