c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-05-23 19:04:45 +03:00
Code Issues Packages Projects Releases Wiki Activity

Extend CONFIG_DEBUG_LOCK_ALLOC check

Browse Source 
The CONFIG_DEBUG_LOCK_ALLOC check at configure time was added to
detect when mutex_lock() is defined as a GPL-only symbol.  However,
the check as written only inferred this from this configuration
setting, it never actually checked.  This change introduces that
missing check to prevent false positives.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This commit is contained in:
Brian Behlendorf
2012-05-21 12:59:58 -07:00
parent c421831192
commit e5b8562277
2 changed files with 244 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files
config/kernel.m4
+62 -22
View File
@@ -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.
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 #
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.]), [])
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])
])
ZFS_AC_KERNEL_CONFIG_PREEMPT
ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC
])
dnl #
dnl # Check CONFIG_PREEMPT
dnl #
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_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.]), [])
])
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 #