From d878a66a9a77fc67801000bfab8fa77b2b3faecc Mon Sep 17 00:00:00 2001
From: Chuck Tuffli <chuck@FreeBSD.org>
Date: Fri, 5 Mar 2021 08:13:23 -0800
Subject: [PATCH] wait for device mounts in zpool and dumpon

If the root file system is composed from multiple devices, wait for
devices to be ready before running zpool and dumpon rc scripts.

An example of this is if the bulk of the root file system exists on a
fast device (e.g. NVMe) but the /var directory comes from a ZFS dataset
on a slower device (e.g. SATA). In this case, it is possible that the
zpool import may run before the slower device has finished being probed,
leaving the system in an intermediate state.

Fix is to add root_hold_wait to the zpool and dumpon (which has a
similar issue) rc scripts.

PR:		242189

(cherry picked from commit f30f11f878fe2aa535cd286810d31c92793a3d95)
---
 libexec/rc/rc.d/dumpon | 2 ++
 libexec/rc/rc.d/zpool  | 9 ++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/libexec/rc/rc.d/dumpon b/libexec/rc/rc.d/dumpon
index a1132c78da6..6ca335b7384 100755
--- a/libexec/rc/rc.d/dumpon
+++ b/libexec/rc/rc.d/dumpon
@@ -55,6 +55,7 @@ dumpon_start()
 	[Nn][Oo] | '')
 		;;
 	[Aa][Uu][Tt][Oo])
+		root_hold_wait
 		dev=$(/bin/kenv -q dumpdev)
 		if [ -n "${dev}" ] ; then
 			dumpon_try "${dev}"
@@ -75,6 +76,7 @@ dumpon_start()
 		return 1
 		;;
 	*)
+		root_hold_wait
 		dumpon_try "${dumpdev}"
 		;;
 	esac
diff --git a/libexec/rc/rc.d/zpool b/libexec/rc/rc.d/zpool
index f98693f2cb1..e73c2b7e5b7 100755
--- a/libexec/rc/rc.d/zpool
+++ b/libexec/rc/rc.d/zpool
@@ -22,7 +22,14 @@ zpool_start()
 
 	for cachefile in /etc/zfs/zpool.cache /boot/zfs/zpool.cache; do
 		if [ -r $cachefile ]; then
-			zpool import -c $cachefile -a -N && break
+			zpool import -c $cachefile -a -N
+			if [ $? -ne 0 ]; then
+				echo "Import of zpool cache ${cachefile} failed," \
+				    "will retry after root mount hold release"
+				root_hold_wait
+				zpool import -c $cachefile -a -N
+			fi
+			break
 		fi
 	done
 }