From 58216f57225315059e38d564a17ec6b656eada60 Mon Sep 17 00:00:00 2001
From: Dennis Camera <dennis.camera@ssrq-sds-fds.ch>
Date: Mon, 22 Mar 2021 09:42:04 +0100
Subject: [PATCH] [type/__ssrq_zfs] Add workaround for bug 11574

https://github.com/openzfs/zfs/issues/11574
---
 type/__ssrq_zfs/explorer/pagesize | 25 +++++++++++++++++++++++++
 type/__ssrq_zfs/manifest          | 23 ++++++++++++++++++++++-
 2 files changed, 47 insertions(+), 1 deletion(-)
 create mode 100755 type/__ssrq_zfs/explorer/pagesize

diff --git a/type/__ssrq_zfs/explorer/pagesize b/type/__ssrq_zfs/explorer/pagesize
new file mode 100755
index 0000000..1bed50b
--- /dev/null
+++ b/type/__ssrq_zfs/explorer/pagesize
@@ -0,0 +1,25 @@
+#!/bin/sh -e
+#
+# 2021 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+getconf PAGESIZE 2>/dev/null ||
+getconf PAGE_SIZE 2>/dev/null || {
+	echo 'Cannot determine pagesize.' >&2
+	exit 1
+}
diff --git a/type/__ssrq_zfs/manifest b/type/__ssrq_zfs/manifest
index 5e13087..a2e0a9b 100755
--- a/type/__ssrq_zfs/manifest
+++ b/type/__ssrq_zfs/manifest
@@ -1,6 +1,6 @@
 #!/bin/sh -e
 #
-# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+# 2020-2021 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
 #
 # This file is part of cdist.
 #
@@ -86,6 +86,27 @@ __block /etc/modprobe.d/zfs.conf:cdist-zfs-tunables \
 $(sed -e 's/^/options zfs /' "${__object:?}/parameter/tunable")
 EOF
 
+
+
+# HACK: Workaround spl bug that exhausts all memory on `zfs scrub' on non-4k
+#       page sizes
+#       https://github.com/openzfs/zfs/issues/11756
+#       https://github.com/openzfs/zfs/issues/11574
+pagesize=$(cat "${__object:?}/explorer/pagesize")
+if test $((pagesize)) -eq $((64 * 1024))
+then
+	spl_kmem_cache_slab_limit=16384
+fi
+require='__package_apt/zfs-modules' \
+__block /etc/modprobe.d/zfs.conf:cdist-spl-workaround-11574 \
+	--state "$(test "${spl_kmem_cache_slab_limit-}" && echo present || echo absent)" \
+	--file /etc/modprobe.d/zfs.conf \
+	--prefix '# cdist:spl-workaround-11574' \
+	--suffix '#/cdist:spl-workaround-11574' \
+	--text - <<EOF
+options spl spl_kmem_cache_slab_limit=$((spl_kmem_cache_slab_limit))
+EOF
+
 set_zed_rc() {
 	require=__package_apt/zfs-zed \
 	__key_value /etc/zfs/zed.d/zed.rc:"$1" \