Make CONFIG_PREEMPT Fatal

[zfs.git] / config / kernel.m4

diff --git a/config/kernel.m4 b/config/kernel.m4
index 492fbab..8b4a5c7 100644 (file)
--- a/config/kernel.m4
+++ b/config/kernel.m4
@@ -274,6 +274,12 @@ AC_DEFUN([ZFS_AC_SPL], [
 ])
 
 dnl #
+dnl # Certain kernel build options are not supported.  These must be
+dnl # detected at configure time and cause a build failure.  Otherwise
+dnl # modules may be successfully built that behave incorrectly.
+dnl #
+dnl # CONFIG_PREEMPT - Preempt kernels require special handling.
+dnl #
 dnl # There are certain kernel build options which when enabled are
 dnl # completely incompatible with non GPL kernel modules.  It is best
 dnl # to detect these at configure time and fail with a clear error
@@ -283,6 +289,11 @@ dnl # CONFIG_DEBUG_LOCK_ALLOC - Maps mutex_lock() to mutex_lock_nested()
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_CONFIG], [
 
+       ZFS_LINUX_CONFIG([PREEMPT],
+               AC_MSG_ERROR([
+               *** Kernel built with CONFIG_PREEMPT which is not supported.
+               ** You must rebuild your kernel without this option.]), [])
+
        if test "$ZFS_META_LICENSE" = CDDL; then
                ZFS_LINUX_CONFIG([DEBUG_LOCK_ALLOC],
                AC_MSG_ERROR([