Description: do not attempt to build the modules on PREEMPT_RT kernels
Author: Andreas Beckmann <anbe@debian.org>
Bug-Debian: https://bugs.debian.org/981212
Bug: https://github.com/openzfs/zfs/issues/11097

Index: zfs-linux/scripts/dkms.mkconf
===================================================================
--- zfs-linux.orig/scripts/dkms.mkconf
+++ zfs-linux/scripts/dkms.mkconf
@@ -25,6 +25,12 @@ PACKAGE_NAME="${pkgname}"
 PACKAGE_VERSION="${pkgver}"
 PACKAGE_CONFIG="${pkgcfg}"
 NO_WEAK_MODULES="yes"
+if [ -f \$kernel_source_dir/.config ]; then
+    . \$kernel_source_dir/.config
+    if [ "\$CONFIG_PREEMPT_RT" = "y" ]; then
+        BUILD_EXCLUSIVE_KERNEL="NOT ON PREEMPT_RT"
+    fi
+fi
 PRE_BUILD="configure
   --prefix=/usr
   --with-config=kernel