diff options
Diffstat (limited to 'config/kernel.m4')
| -rw-r--r-- | config/kernel.m4 | 78 |
1 files changed, 59 insertions, 19 deletions
diff --git a/config/kernel.m4 b/config/kernel.m4 index 48e92ced4..0f6100071 100644 --- a/config/kernel.m4 +++ b/config/kernel.m4 @@ -311,34 +311,74 @@ 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. +AC_DEFUN([ZFS_AC_KERNEL_CONFIG], [ + + AS_IF([test "$ZFS_META_LICENSE" = GPL], [ + AC_DEFINE([HAVE_GPL_ONLY_SYMBOLS], [1], + [Define to 1 if licensed under the GPL]) + ]) + + ZFS_AC_KERNEL_CONFIG_PREEMPT + ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC +]) + dnl # -dnl # There are certain kernel build options which when enabled are -dnl # completely incompatible with non GPL kernel modules. It is best -dnl # to detect these at configure time and fail with a clear error -dnl # rather than build everything and fail during linking. +dnl # Check CONFIG_PREEMPT dnl # -dnl # CONFIG_DEBUG_LOCK_ALLOC - Maps mutex_lock() to mutex_lock_nested() +dnl # Premptible kernels will be supported in the future. But at the +dnl # moment there are a few places in the code which need to be updated +dnl # to accomidate them. Until that work occurs we should detect this +dnl # at configure time and fail with a sensible message. Otherwise, +dnl # people will be able to build successfully, however they will have +dnl # stability problems. See https://github.com/zfsonlinux/zfs/issues/83 dnl # -AC_DEFUN([ZFS_AC_KERNEL_CONFIG], [ +AC_DEFUN([ZFS_AC_KERNEL_CONFIG_PREEMPT], [ ZFS_LINUX_CONFIG([PREEMPT], AC_MSG_ERROR([ *** Kernel built with CONFIG_PREEMPT which is not supported. *** You must rebuild your kernel without this option.]), []) +]) - AS_IF([test "$ZFS_META_LICENSE" = CDDL], [ - ZFS_LINUX_CONFIG([DEBUG_LOCK_ALLOC], - AC_MSG_ERROR([ - *** Kernel built with CONFIG_DEBUG_LOCK_ALLOC which is - *** incompatible with the CDDL license. You must rebuild - *** your kernel without this option.]), []) - ]) - - AS_IF([test "$ZFS_META_LICENSE" = GPL], [ - AC_DEFINE([HAVE_GPL_ONLY_SYMBOLS], [1], - [Define to 1 if licensed under the GPL]) - ]) +dnl # +dnl # Check CONFIG_DEBUG_LOCK_ALLOC +dnl # +dnl # This is typically only set for debug kernels because it comes with +dnl # a performance penalty. However, when it is set it maps the non-GPL +dnl # symbol mutex_lock() to the GPL-only mutex_lock_nested() symbol. +dnl # This will cause a failure at link time which we'd rather know about +dnl # at compile time. +dnl # +dnl # Since we plan to pursue making mutex_lock_nested() a non-GPL symbol +dnl # with the upstream community we add a check to detect this case. +dnl # +AC_DEFUN([ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC], [ + + ZFS_LINUX_CONFIG([DEBUG_LOCK_ALLOC], [ + AC_MSG_CHECKING([whether mutex_lock() is GPL-only]) + tmp_flags="$EXTRA_KCFLAGS" + ZFS_LINUX_TRY_COMPILE([ + #include <linux/module.h> + #include <linux/mutex.h> + + MODULE_LICENSE("$ZFS_META_LICENSE"); + ],[ + struct mutex lock; + + mutex_init(&lock); + mutex_lock(&lock); + mutex_unlock(&lock); + ],[ + AC_MSG_RESULT(no) + ],[ + AC_MSG_RESULT(yes) + AC_MSG_ERROR([ + *** Kernel built with CONFIG_DEBUG_LOCK_ALLOC which is incompatible + *** with the CDDL license. You must rebuild your kernel without + *** this option enabled.]) + ]) + EXTRA_KCFLAGS="$tmp_flags" + ], []) ]) dnl # |