diff mbox series

[ovs-dev,RFC,1/6] acinclude.m4: Remove support for building the OVS kernel module

Message ID 20220415214245.18948-2-gvrose8192@gmail.com
State Changes Requested
Headers show
Series Remove OVS kernel driver | expand

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Commit Message

Gregory Rose April 15, 2022, 9:42 p.m. UTC 
Since the openvswitch project inception it has had support for building
a Linux kernel module to support the OVS kernel datapath.  Since Linux
kernel release 5.8 support for newer kernels has been deprecated.  Now
is the time to fully discontinue support for building the openvswitch
kernel driver. Since Linux 5.9 the Linux built-in openvswitch kernel
driver supports all necessary features and functions of the kernel
datapath and the need to support this additional "out of tree" kernel
module is gone.

Remove the --with-linux configuration support from the acinclude.m4
configuration and warn user it is not supported any longer.

Signed-off-by: Greg Rose <gvrose8192@gmail.com>
---
 acinclude.m4 | 683 +--------------------------------------------------
 1 file changed, 1 insertion(+), 682 deletions(-)
diff mbox series

Patch

diff --git a/acinclude.m4 b/acinclude.m4
index 61e88105f..0b1be92f7 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -117,132 +117,11 @@  dnl OVS_CHECK_LINUX
 dnl
 dnl Configure linux kernel source tree
 AC_DEFUN([OVS_CHECK_LINUX], [
-  AC_ARG_WITH([linux],
-              [AC_HELP_STRING([--with-linux=/path/to/linux],
-                              [Specify the Linux kernel build directory])])
-  AC_ARG_WITH([linux-source],
-              [AC_HELP_STRING([--with-linux-source=/path/to/linux-source],
-                              [Specify the Linux kernel source directory
-                               (usually figured out automatically from build
-                               directory)])])
-
-  # Deprecated equivalents to --with-linux, --with-linux-source.
-  AC_ARG_WITH([l26])
-  AC_ARG_WITH([l26-source])
-
   if test X"$with_linux" != X; then
-    KBUILD=$with_linux
-    AC_MSG_WARN([--with-linux is deprecated and kernel support is limited to 5.8 and below])
-  elif test X"$with_l26" != X; then
-    KBUILD=$with_l26
-    AC_MSG_WARN([--with-l26 is deprecated, please use --with-linux instead])
-  else
+    AC_MSG_WARN([--with-linux is no longer supported])
     KBUILD=
   fi
 
-  if test X"$KBUILD" != X; then
-    if test X"$with_linux_source" != X; then
-      KSRC=$with_linux_source
-    elif test X"$with_l26_source" != X; then
-      KSRC=$with_l26_source
-      AC_MSG_WARN([--with-l26-source is deprecated, please use --with-linux-source instead])
-    else
-      KSRC=
-    fi
-  elif test X"$with_linux_source" != X || test X"$with_l26_source" != X; then
-    AC_MSG_ERROR([Linux source directory may not be specified without Linux build directory])
-  fi
-
-  if test -n "$KBUILD"; then
-    KBUILD=`eval echo "$KBUILD"`
-    case $KBUILD in
-        /*) ;;
-        *) KBUILD=`pwd`/$KBUILD ;;
-    esac
-
-    # The build directory is what the user provided.
-    # Make sure that it exists.
-    AC_MSG_CHECKING([for Linux build directory])
-    if test -d "$KBUILD"; then
-        AC_MSG_RESULT([$KBUILD])
-        AC_SUBST(KBUILD)
-    else
-        AC_MSG_RESULT([no])
-        AC_ERROR([source dir $KBUILD doesn't exist])
-    fi
-
-    # Debian breaks kernel headers into "source" header and "build" headers.
-    # We want the source headers, but $KBUILD gives us the "build" headers.
-    # Use heuristics to find the source headers.
-    AC_MSG_CHECKING([for Linux source directory])
-    if test -n "$KSRC"; then
-      KSRC=`eval echo "$KSRC"`
-      case $KSRC in
-          /*) ;;
-          *) KSRC=`pwd`/$KSRC ;;
-      esac
-      if test ! -e $KSRC/include/linux/kernel.h; then
-        AC_MSG_ERROR([$KSRC is not a kernel source directory])
-      fi
-    else
-      KSRC=$KBUILD
-      if test ! -e $KSRC/include/linux/kernel.h; then
-        # Debian kernel build Makefiles tend to include a line of the form:
-        # MAKEARGS := -C /usr/src/linux-headers-3.2.0-1-common O=/usr/src/linux-headers-3.2.0-1-486
-        # First try to extract the source directory from this line.
-        KSRC=`sed -n 's/.*-C \([[^ ]]*\).*/\1/p' "$KBUILD"/Makefile`
-        if test ! -e "$KSRC"/include/linux/kernel.h; then
-          # Didn't work.  Fall back to name-based heuristics that used to work.
-          case `echo "$KBUILD" | sed 's,/*$,,'` in # (
-            */build)
-              KSRC=`echo "$KBUILD" | sed 's,/build/*$,/source,'`
-              ;; # (
-            *)
-              KSRC=`(cd $KBUILD && pwd -P) | sed 's,-[[^-]]*$,-common,'`
-              ;;
-          esac
-        fi
-      fi
-      if test ! -e "$KSRC"/include/linux/kernel.h; then
-        AC_MSG_ERROR([cannot find source directory (please use --with-linux-source)])
-      fi
-    fi
-    AC_MSG_RESULT([$KSRC])
-
-    AC_MSG_CHECKING([for kernel version])
-    version=`sed -n 's/^VERSION = //p' "$KSRC/Makefile"`
-    patchlevel=`sed -n 's/^PATCHLEVEL = //p' "$KSRC/Makefile"`
-    sublevel=`sed -n 's/^SUBLEVEL = //p' "$KSRC/Makefile"`
-    if test X"$version" = X || test X"$patchlevel" = X; then
-       AC_ERROR([cannot determine kernel version])
-    elif test X"$sublevel" = X; then
-       kversion=$version.$patchlevel
-    else
-       kversion=$version.$patchlevel.$sublevel
-    fi
-    AC_MSG_RESULT([$kversion])
-
-    if test "$version" -ge 5; then
-       if test "$version" = 5 && test "$patchlevel" -le 8; then
-          : # Linux 5.x
-       else
-          AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version newer than 5.8.x is not supported (please refer to the FAQ for advice)])
-       fi
-    elif test "$version" = 4; then
-       : # Linux 4.x
-    elif test "$version" = 3 && test "$patchlevel" -ge 10; then
-       : # Linux 3.x
-    else
-       AC_ERROR([Linux kernel in $KBUILD is version $kversion, but version 3.10 or later is required])
-    fi
-    if (test ! -e "$KBUILD"/include/linux/version.h && \
-        test ! -e "$KBUILD"/include/generated/uapi/linux/version.h)|| \
-       (test ! -e "$KBUILD"/include/linux/autoconf.h && \
-        test ! -e "$KBUILD"/include/generated/autoconf.h); then
-        AC_MSG_ERROR([Linux kernel source in $KBUILD is not configured])
-    fi
-    OVS_CHECK_LINUX_COMPAT
-  fi
   AM_CONDITIONAL(LINUX_ENABLED, test -n "$KBUILD")
 ])
 
@@ -665,566 +544,6 @@  AC_DEFUN([OVS_FIND_OP_PARAM_IFELSE], [
   fi
 ])
 
-dnl OVS_DEFINE(NAME)
-dnl
-dnl Defines NAME to 1 in kcompat.h.
-AC_DEFUN([OVS_DEFINE], [
-  echo '#define $1 1' >> datapath/linux/kcompat.h.new
-])
-
-dnl OVS_CHECK_LINUX_COMPAT
-dnl
-dnl Runs various Autoconf checks on the Linux kernel source in
-dnl the directory in $KBUILD.
-AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
-  rm -f datapath/linux/kcompat.h.new
-  mkdir -p datapath/linux
-  : > datapath/linux/kcompat.h.new
-
-  echo '#include <linux/version.h>
-#ifndef RHEL_RELEASE_CODE
-#define RHEL_RELEASE_CODE 0
-#define RHEL_RELEASE_VERSION(a, b) 0
-#endif' >> datapath/linux/kcompat.h.new
-
-  OVS_GREP_IFELSE([$KSRC/arch/x86/include/asm/checksum_32.h], [src_err,],
-                  [OVS_DEFINE([HAVE_CSUM_COPY_DBG])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/ip6_fib.h], [rt6_get_cookie],
-                  [OVS_DEFINE([HAVE_RT6_GET_COOKIE])])
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/addrconf.h], [ipv6_stub],
-                        [dst_entry])
-  OVS_GREP_IFELSE([$KSRC/include/net/addrconf.h], [ipv6_dst_lookup.*net],
-                  [OVS_DEFINE([HAVE_IPV6_DST_LOOKUP_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/addrconf.h], [ipv6_dst_lookup_flow.*net],
-                  [OVS_DEFINE([HAVE_IPV6_DST_LOOKUP_FLOW_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/addrconf.h], [ipv6_stub])
-  OVS_GREP_IFELSE([$KSRC/include/net/addrconf.h], [ipv6_dst_lookup_flow])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [ERR_CAST])
-  OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [IS_ERR_OR_NULL])
-  OVS_GREP_IFELSE([$KSRC/include/linux/err.h], [PTR_ERR_OR_ZERO])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/jump_label.h], [static_branch_unlikely(],
-                  [OVS_DEFINE([HAVE_UPSTREAM_STATIC_KEY])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/jump_label.h], [DEFINE_STATIC_KEY_FALSE],
-                  [OVS_DEFINE([HAVE_DEFINE_STATIC_KEY])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/jump_label.h],
-                  [DECLARE_STATIC_KEY_FALSE],
-                  [OVS_DEFINE([HAVE_DECLARE_STATIC_KEY])])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [eth_hw_addr_random])
-  OVS_GREP_IFELSE([$KSRC/include/linux/etherdevice.h], [ether_addr_copy])
-
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_link.h], [IFLA_GENEVE_TOS])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_link.h], [rtnl_link_stats64])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_link.h], [rtnl_link_stats64])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_set_encap_proto])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_hwaccel_push_inside])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [__vlan_hwaccel_clear_tag])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/in.h], [ipv4_is_multicast])
-  OVS_GREP_IFELSE([$KSRC/include/linux/in.h], [proto_ports_offset])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [__ip_select_ident.*dst_entry],
-                  [OVS_DEFINE([HAVE_IP_SELECT_IDENT_USING_DST_ENTRY])])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [__ip_select_ident.*net],
-                  [OVS_DEFINE([HAVE_IP_SELECT_IDENT_USING_NET])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [inet_get_local_port_range.*net],
-                  [OVS_DEFINE([HAVE_INET_GET_LOCAL_PORT_RANGE_USING_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [ip_defrag.*net],
-                  [OVS_DEFINE([HAVE_IP_DEFRAG_TAKES_NET])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/ip.h],
-                        [ip_do_fragment], [net],
-                        [OVS_DEFINE([HAVE_IP_DO_FRAGMENT_TAKES_NET])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/ip.h],
-                        [ip_local_out], [net],
-                        [OVS_DEFINE([HAVE_IP_LOCAL_OUT_TAKES_NET])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [ip_skb_dst_mtu])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/ip.h], [IPSKB_FRAG_PMTU],
-                  [OVS_DEFINE([HAVE_CORRECT_MRU_HANDLING])])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip_tunnels.h], [__ip_tunnel_change_mtu])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [hashfn.*const],
-                  [OVS_DEFINE([HAVE_INET_FRAGS_CONST])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [last_in],
-                  [OVS_DEFINE([HAVE_INET_FRAGS_LAST_IN])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frag_evicting])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frag_evictor])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frags],
-                        [frags_work])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frags],
-                        [rwlock])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frag_queue],
-                        [list_evictor])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frag_lru_move])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/inet_frag.h],
-                        [sub_frag_mem_limit], [struct.netns_frags],
-                        [OVS_DEFINE([HAVE_SUB_FRAG_MEM_LIMIT_ARG_STRUCT_NETNS_FRAGS])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [void.*inet_frags_init],
-                  [OVS_DEFINE([HAVE_VOID_INET_FRAGS_INIT])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inetpeer.h], [vif],
-                  [OVS_DEFINE([HAVE_INETPEER_VIF_SUPPORT])])
-
-  dnl Check for dst_cache and ipv6 lable to use backported tunnel infrastructure.
-  dnl OVS does not really need ipv6 label field, but its presence signifies that
-  dnl the stack has all required ipv6 support.
-  dnl OVS also does not need dst_cache But this dependency allows us to write
-  dnl much cleaner code.
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/ip_tunnels.h], [ip_tunnel_key],
-                        [label],
-                        [OVS_GREP_IFELSE([$KSRC/include/net/ip_tunnels.h],
-                                         [iptunnel_pull_offloads],
-                        [OVS_GREP_IFELSE([$KSRC/include/net/dst_cache.h], [dst_cache],
-                        [OVS_GREP_IFELSE([$KSRC/include/net/erspan.h], [erspan_md2],
-                                         [OVS_DEFINE([USE_UPSTREAM_TUNNEL])])])])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/dst_cache.h], [dst_cache],
-                  [OVS_DEFINE([USE_BUILTIN_DST_CACHE])])
-  OVS_GREP_IFELSE([$KSRC/include/net/mpls.h], [mpls_hdr],
-                  [OVS_DEFINE([MPLS_HEADER_IS_L3])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/net.h], [sock_create_kern.*net],
-                  [OVS_DEFINE([HAVE_SOCK_CREATE_KERN_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_fill_metadata_dst])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_disable_lro])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_stats])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_get_by_index_rcu])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [dev_recursion_level])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [__skb_gso_segment])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [skb_gso_error_unwind])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [can_checksum_protocol])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_get_iflink])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_features_check],
-                  [OVS_DEFINE([USE_UPSTREAM_TUNNEL_GSO])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_add_vxlan_port])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_add_geneve_port])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [ndo_udp_tunnel_add])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [netdev_features_t])
-  dnl Ubuntu kernel 3.13 has defined this struct but not used for netdev->tstats.
-  dnl So check type of tstats.
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [pcpu_sw_netstats.*tstats],
-                  [OVS_DEFINE([HAVE_PCPU_SW_NETSTATS])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [netif_needs_gso.*net_device],
-                  [OVS_DEFINE([HAVE_NETIF_NEEDS_GSO_NETDEV])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [skb_csum_hwoffload_help])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [udp_offload])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [udp_offload.*uoff],
-                  [OVS_DEFINE([HAVE_UDP_OFFLOAD_ARG_UOFF])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [gro_remcsum])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h], [IFF_PHONY_HEADROOM])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device_ops],
-                        [extended])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/linux/netdevice.h],
-                        [netdev_master_upper_dev_link], [upper_priv],
-                        [OVS_DEFINE([HAVE_NETDEV_MASTER_UPPER_DEV_LINK_PRIV])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h],
-                  [netdev_master_upper_dev_link_rh],
-                  [OVS_DEFINE([HAVE_NETDEV_MASTER_UPPER_DEV_LINK_RH])])
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device],
-                        [max_mtu])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device_ops_extended],
-                        [ndo_change_mtu], [OVS_DEFINE([HAVE_RHEL7_MAX_MTU])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/linux/netdevice.h],
-                        [dev_change_flags], [extack],
-                        [OVS_DEFINE([HAVE_DEV_CHANGE_FLAGS_TAKES_EXTACK])])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hook_state])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hook_state],
-                        [struct net ], [OVS_DEFINE([HAVE_NF_HOOK_STATE_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netfilter.h], [nf_register_net_hook])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hookfn.*nf_hook_ops],
-                  [OVS_DEFINE([HAVE_NF_HOOKFN_ARG_OPS])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hookfn], [priv],
-                  [OVS_DEFINE([HAVE_NF_HOOKFN_ARG_PRIV])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hook_ops],
-                        [owner], [OVS_DEFINE([HAVE_NF_HOOKS_OPS_OWNER])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netfilter.h], [NFPROTO_INET])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netfilter.h], [CONFIG_NF_NAT_NEEDED])
-
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netfilter_ipv6.h], [nf_ipv6_ops],
-                        [fragment.*sock], [OVS_DEFINE([HAVE_NF_IPV6_OPS_FRAGMENT])])
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                        [nf_conn], [struct timer_list[[ \t]]*timeout],
-                        [OVS_DEFINE([HAVE_NF_CONN_TIMER])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_delete(], [OVS_DEFINE([HAVE_NF_CT_DELETE])])
-
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_tmpl_alloc], [nf_conntrack_zone],
-                  [OVS_DEFINE([HAVE_NF_CT_TMPL_ALLOC_TAKES_STRUCT_ZONE])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_get_tuplepr], [struct.net],
-                  [OVS_DEFINE([HAVE_NF_CT_GET_TUPLEPR_TAKES_STRUCT_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_set])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_is_untracked])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack.h],
-                  [nf_ct_invert_tuplepr])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_zones.h],
-                  [nf_ct_zone_init])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_l3proto.h],
-                  [net_ns_get])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_labels.h],
-                  [nf_connlabels_get])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_labels.h],
-                  [nf_connlabels_get], [int bit],
-                  [OVS_DEFINE([HAVE_NF_CONNLABELS_GET_TAKES_BIT])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_labels.h],
-                        [nf_conn_labels], [words])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_nat.h], [nf_ct_nat_ext_add])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_nat.h], [nf_nat_alloc_null_binding])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_nat.h], [nf_nat_range2])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_nat.h], [nf_nat_packet],
-                  [OVS_DEFINE([HAVE_UPSTREAM_NF_NAT])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_seqadj.h], [nf_ct_seq_adjust])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_count.h], [nf_conncount_gc_list],
-                  [OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_count.h],
-                                   [int nf_conncount_add],
-                                   [], [OVS_DEFINE([HAVE_UPSTREAM_NF_CONNCOUNT])])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_timeout.h], [nf_ct_set_timeout])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_timeout.h], [struct nf_ct_timeout],
-                  [OVS_DEFINE([HAVE_NF_CT_TIMEOUT])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_timeout.h],
-                        [\(*nf_ct_timeout_find_get_hook\)], [net],
-                        [OVS_DEFINE([HAVE_NF_CT_TIMEOUT_FIND_GET_HOOK_NET])])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/random.h],
-                  [prandom_u32[[\(]]],
-                  [OVS_DEFINE([HAVE_PRANDOM_U32])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/random.h], [prandom_u32_max])
-  OVS_GREP_IFELSE([$KSRC/include/linux/prandom.h],
-                  [prandom_u32[[\(]]],
-                  [OVS_DEFINE([HAVE_PRANDOM_U32])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/prandom.h], [prandom_u32_max])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/rtnetlink.h], [get_link_net])
-  OVS_GREP_IFELSE([$KSRC/include/net/rtnetlink.h], [name_assign_type])
-  OVS_GREP_IFELSE([$KSRC/include/net/rtnetlink.h], [rtnl_create_link.*src_net],
-                  [OVS_DEFINE([HAVE_RTNL_CREATE_LINK_SRC_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/net_namespace.h], [possible_net_t])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/rcupdate.h], [rcu_read_lock_held], [],
-                  [OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h],
-                                   [rcu_read_lock_held])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h], [lockdep_rtnl_is_held])
-  OVS_GREP_IFELSE([$KSRC/include/linux/rtnetlink.h], [net_rwsem])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/rtnetlink.h],
-                        [rtnl_create_link], [extack],
-                        [OVS_DEFINE([HAVE_RTNL_CREATE_LINK_TAKES_EXTACK])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [nf_reset_ct])
-
-  # Check for the proto_data_valid member in struct sk_buff.  The [^@]
-  # is necessary because some versions of this header remove the
-  # member but retain the kerneldoc comment that describes it (which
-  # starts with @).  The brackets must be doubled because of m4
-  # quoting rules.
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [[[^@]]proto_data_valid],
-                  [OVS_DEFINE([HAVE_PROTO_DATA_VALID])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_checksum_start_offset])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [inner_protocol])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [inner_protocol_type])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_inner_transport_offset])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [kfree_skb_list])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [rxhash])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [u16.*rxhash],
-                  [OVS_DEFINE([HAVE_U16_RXHASH])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_dst(],
-                  [OVS_DEFINE([HAVE_SKB_DST_ACCESSOR_FUNCS])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [skb_copy_from_linear_data_offset])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [skb_reset_tail_pointer])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_cow_head])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_warn_if_lro],
-                  [OVS_DEFINE([HAVE_SKB_WARN_LRO])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [consume_skb])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_frag_page])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_has_frag_list])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [__skb_fill_page_desc])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_reset_mac_len])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_unclone])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_orphan_frags])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_get_hash(],
-                  [OVS_DEFINE([HAVE_SKB_GET_HASH])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_clear_hash])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [int.skb_zerocopy(],
-                  [OVS_DEFINE([HAVE_SKB_ZEROCOPY])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_ensure_writable])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_vlan_pop])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [__skb_vlan_pop])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_vlan_push])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_clear_hash_if_not_l4])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_postpush_rcsum])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [lco_csum])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_nfct])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_put_zero])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/types.h], [__wsum],
-                  [OVS_DEFINE([HAVE_CSUM_TYPES])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/types.h], [__wsum],
-                  [OVS_DEFINE([HAVE_CSUM_TYPES])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_replace4])
-  OVS_GREP_IFELSE([$KSRC/include/net/checksum.h], [csum_unfold])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/dst.h], [dst_discard_sk])
-  OVS_GREP_IFELSE([$KSRC/include/net/dst.h], [__skb_dst_copy])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [genl_has_listeners])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [mcgrp_offset])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [parallel_ops])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [netlink_has_listeners(net->genl_sock],
-                  [OVS_DEFINE([HAVE_GENL_HAS_LISTENERS_TAKES_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [genlmsg_parse])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [genl_notify.*family],
-                  [OVS_DEFINE([HAVE_GENL_NOTIFY_TAKES_FAMILY])])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [genl_validate_flags])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/genetlink.h],
-                        [genl_notify], [net],
-                        [OVS_DEFINE([HAVE_GENL_NOTIFY_TAKES_NET])])
-
-
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/genetlink.h],
-                        [genl_multicast_group], [id])
-  OVS_GREP_IFELSE([$KSRC/include/net/geneve.h], [geneve_hdr])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/gre.h], [gre_cisco_register])
-  OVS_GREP_IFELSE([$KSRC/include/net/gre.h], [gre_handle_offloads])
-  OVS_GREP_IFELSE([$KSRC/include/net/ipv6.h], [IP6_FH_F_SKIP_RH])
-  OVS_GREP_IFELSE([$KSRC/include/net/ipv6.h], [ip6_local_out_sk])
-  OVS_GREP_IFELSE([$KSRC/include/net/ipv6.h], [__ipv6_addr_jhash])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip6_fib.h], [rt6i.*u.dst],
-                  [OVS_DEFINE([HAVE_RT6INFO_DST_UNION])])
-  OVS_GREP_IFELSE([$KSRC/include/net/ip6_route.h], [ip6_frag.*sock],
-                  [OVS_DEFINE([HAVE_IP_FRAGMENT_TAKES_SOCK])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_64bit])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_get_be16])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be16])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be32])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_be64])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_put_in_addr])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_find_nested])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_is_last])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h], [nla_nest_start_noflag])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netlink.h], [void.*netlink_set_err],
-                  [OVS_DEFINE([HAVE_VOID_NETLINK_SET_ERR])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netlink.h],
-                        [nla_parse], [netlink_ext_ack],
-                        [OVS_DEFINE([HAVE_NETLINK_EXT_ACK])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/sctp/checksum.h], [sctp_compute_cksum])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_insert_tag_set_proto])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [__vlan_insert_tag])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [vlan_get_protocol])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [skb_vlan_tagged])
-  OVS_GREP_IFELSE([$KSRC/include/linux/if_vlan.h], [eth_type_vlan])
-
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/dst_metadata.h],
-                        [metadata_dst_alloc], [metadata_type])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/u64_stats_sync.h], [u64_stats_fetch_begin_irq])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/vxlan.h], [struct vxlan_metadata],
-                  [OVS_DEFINE([HAVE_VXLAN_METADATA])])
-  OVS_GREP_IFELSE([$KSRC/include/net/udp.h], [udp_flow_src_port],
-                  [OVS_GREP_IFELSE([$KSRC/include/net/udp.h], [inet_get_local_port_range(net],
-                                   [OVS_DEFINE([HAVE_UDP_FLOW_SRC_PORT])])])
-  OVS_GREP_IFELSE([$KSRC/include/net/udp.h], [udp_v4_check])
-  OVS_GREP_IFELSE([$KSRC/include/net/udp_tunnel.h], [udp_tunnel_gro_complete])
-  OVS_GREP_IFELSE([$KSRC/include/net/udp_tunnel.h], [sk_buff.*udp_tunnel_handle_offloads],
-                  [OVS_DEFINE([HAVE_UDP_TUNNEL_HANDLE_OFFLOAD_RET_SKB])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/udp_tunnel.h], [udp_tunnel_sock_cfg],
-                        [gro_receive])
-
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [ignore_df],
-                  [OVS_DEFINE([HAVE_IGNORE_DF_RENAME])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/netdevice.h], [NET_NAME_UNKNOWN],
-                  [OVS_DEFINE([HAVE_NET_NAME_UNKNOWN])])
-
-  OVS_GREP_IFELSE([$KSRC/include/net/sock.h], [sk_no_check_tx])
-  OVS_GREP_IFELSE([$KSRC/include/linux/udp.h], [no_check6_tx])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/protocol.h],
-                        [udp_add_offload], [net],
-                        [OVS_DEFINE([HAVE_UDP_ADD_OFFLOAD_TAKES_NET])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/ipv6/nf_defrag_ipv6.h],
-                        [nf_defrag_ipv6_enable], [net],
-                        [OVS_DEFINE([HAVE_DEFRAG_ENABLE_TAKES_NET])])
-  OVS_GREP_IFELSE([$KSRC/include/net/genetlink.h], [family_list],
-                        [OVS_DEFINE([HAVE_GENL_FAMILY_LIST])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device],
-                        [needs_free_netdev],
-                        [OVS_DEFINE([HAVE_NEEDS_FREE_NETDEV])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/vxlan.h], [vxlan_dev], [cfg],
-                        [OVS_DEFINE([HAVE_VXLAN_DEV_CFG])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_helper.h],
-                  [nf_conntrack_helper_put],
-                  [OVS_DEFINE(HAVE_NF_CONNTRACK_HELPER_PUT)])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_helper.h],
-                  [nf_nat_helper_try_module_get])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_helper.h],
-                  [nf_nat_helper_put])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],[[[[:space:]]]SKB_GSO_UDP[[[:space:]]]],
-                  [OVS_DEFINE([HAVE_SKB_GSO_UDP])])
-  OVS_GREP_IFELSE([$KSRC/include/net/dst.h],[DST_NOCACHE],
-                  [OVS_DEFINE([HAVE_DST_NOCACHE])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/rtnetlink.h], [rtnl_link_ops],
-                        [extack],
-                  [OVS_DEFINE([HAVE_EXT_ACK_IN_RTNL_LINKOPS])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netfilter.h], [nf_hook_ops],
-                        [list],
-                        [OVS_DEFINE([HAVE_LIST_IN_NF_HOOK_OPS])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/netfilter/nf_conntrack_common.h],
-                  [IP_CT_UNTRACKED])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/linux/netdevice.h],
-                        [netdev_master_upper_dev_link], [extack],
-                        [OVS_DEFINE([HAVE_UPPER_DEV_LINK_EXTACK])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/compiler_types.h],
-                  [__LINUX_COMPILER_TYPES_H],
-                  [OVS_DEFINE([HAVE_LINUX_COMPILER_TYPES_H])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/timekeeping.h],
-                  [ktime_get_ts64],
-                  [OVS_DEFINE([HAVE_KTIME_GET_TS64])])
-  OVS_GREP_IFELSE([$KSRC/include/net/net_namespace.h],
-                  [EXPORT_SYMBOL_GPL(peernet2id_alloc)],
-                  [OVS_DEFINE([HAVE_PEERNET2ID_ALLOC])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/timekeeping.h],
-                  [ktime_get_ns],
-                  [OVS_DEFINE([HAVE_KTIME_GET_NS])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h],
-                  frag_percpu_counter_batch[],
-                  [OVS_DEFINE([HAVE_FRAG_PERCPU_COUNTER_BATCH])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [null_compute_pseudo],
-                  [OVS_DEFINE([HAVE_NULL_COMPUTE_PSEUDO])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [__skb_checksum_convert],
-                  [OVS_DEFINE([HAVE_SKB_CHECKSUM_CONVERT])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device],
-                        [max_mtu],
-                        [OVS_DEFINE([HAVE_NET_DEVICE_MAX_MTU])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/ip6_tunnel.h], [__ip6_tnl_parm],
-                        [erspan_ver],
-                        [OVS_DEFINE([HAVE_IP6_TNL_PARM_ERSPAN_VER])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [SKB_GSO_IPXIP6],
-                  [OVS_DEFINE([HAVE_SKB_GSO_IPXIP6])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/ipv6.h],
-                        [ip6_make_flowlabel], [fl6],
-                        [OVS_DEFINE([HAVE_IP6_MAKE_FLOWLABEL_FL6])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/ipv6.h], [netns_sysctl_ipv6],
-                        [auto_flowlabels],
-                        [OVS_DEFINE([HAVE_NETNS_SYSCTL_IPV6_AUTO_FLOWLABELS])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h],
-                  [netif_keep_dst],
-                  [OVS_DEFINE([HAVE_NETIF_KEEP_DST])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/netdevice.h], [net_device_ops],
-                        [ndo_get_iflink],
-                        [OVS_DEFINE([HAVE_NDO_GET_IFLINK])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [skb_set_inner_ipproto],
-                  [OVS_DEFINE([HAVE_SKB_SET_INNER_IPPROTO])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [tunnel_encap_types],
-                  [OVS_DEFINE([HAVE_TUNNEL_ENCAP_TYPES])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_IPTUN_ENCAP_TYPE],
-                  [OVS_DEFINE([HAVE_IFLA_IPTUN_ENCAP_TYPE])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_IPTUN_COLLECT_METADATA],
-                  [OVS_DEFINE([HAVE_IFLA_IPTUN_COLLECT_METADATA])])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_ENCAP_DPORT])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_COLLECT_METADATA])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_IGNORE_DF])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_FWMARK])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_ERSPAN_INDEX])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_GRE_ERSPAN_HWID])
-  OVS_GREP_IFELSE([$KSRC/include/uapi/linux/if_tunnel.h],
-                  [IFLA_IPTUN_FWMARK])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/skbuff.h], [sk_buff],
-                        [csum_valid],
-                        [OVS_DEFINE([HAVE_SKBUFF_CSUM_VALID])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/linux/skbuff.h], [sk_buff],
-                        [vlan_present],
-                        [OVS_DEFINE([HAVE_SKBUFF_VLAN_PRESENT])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [skb_checksum_simple_validate])
-  OVS_GREP_IFELSE([$KSRC/include/linux/netdevice.h],
-                  [void.*ndo_get_stats64],
-                  [OVS_DEFINE([HAVE_VOID_NDO_GET_STATS64])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/timer.h], [init_timer_deferrable],
-                  [OVS_DEFINE([HAVE_INIT_TIMER_DEFERRABLE])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/ip_tunnels.h],
-                        [ip_tunnel_info_opts_set], [flags],
-                        [OVS_DEFINE([HAVE_IP_TUNNEL_INFO_OPTS_SET_FLAGS])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/inet_frag.h], [inet_frags],
-                        [rnd],
-                        [OVS_DEFINE([HAVE_INET_FRAGS_RND])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/overflow.h], [__LINUX_OVERFLOW_H],
-                  [OVS_DEFINE([HAVE_OVERFLOW_H])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/overflow.h], [struct_size],
-                  [OVS_DEFINE([HAVE_STRUCT_SIZE])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/mm.h], [kvmalloc_array],
-                  [OVS_DEFINE([HAVE_KVMALLOC_ARRAY])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/mm.h], [kvmalloc_node],
-                  [OVS_DEFINE([HAVE_KVMALLOC_NODE])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_l3proto.h],
-                  [nf_conntrack_l3proto],
-                  [OVS_DEFINE([HAVE_NF_CONNTRACK_L3PROATO_H])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_core.h],
-                        [nf_conntrack_in], [nf_hook_state],
-                        [OVS_DEFINE([HAVE_NF_CONNTRACK_IN_TAKES_NF_HOOK_STATE])])
-  OVS_GREP_IFELSE([$KSRC/include/net/ipv6_frag.h], [IP6_DEFRAG_CONNTRACK_IN],
-                  [OVS_DEFINE([HAVE_IPV6_FRAG_H])])
-  OVS_FIND_PARAM_IFELSE([$KSRC/include/net/netfilter/nf_conntrack_helper.h],
-                        [nf_ct_helper_ext_add], [nf_conntrack_helper],
-                        [OVS_DEFINE([HAVE_NF_CT_HELPER_EXT_ADD_TAKES_HELPER])])
-  OVS_GREP_IFELSE([$KSRC/include/net/gre.h], [gre_calc_hlen],
-                  [OVS_DEFINE([HAVE_GRE_CALC_HLEN])])
-  OVS_GREP_IFELSE([$KSRC/include/net/gre.h], [ip_gre_calc_hlen],
-                  [OVS_DEFINE([HAVE_IP_GRE_CALC_HLEN])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/rbtree.h], [rb_link_node_rcu],
-                  [OVS_DEFINE([HAVE_RBTREE_RB_LINK_NODE_RCU])])
-  OVS_GREP_IFELSE([$KSRC/include/net/dst_ops.h], [bool confirm_neigh],
-                  [OVS_DEFINE([HAVE_DST_OPS_CONFIRM_NEIGH])])
-  OVS_GREP_IFELSE([$KSRC/include/net/inet_frag.h], [fqdir],
-                  [OVS_DEFINE([HAVE_INET_FRAG_FQDIR])])
-  OVS_FIND_FIELD_IFELSE([$KSRC/include/net/genetlink.h], [genl_ops],
-                        [policy],
-                        [OVS_DEFINE([HAVE_GENL_OPS_POLICY])])
-  OVS_GREP_IFELSE([$KSRC/include/net/netlink.h],
-                  [nla_parse_deprecated_strict],
-                  [OVS_DEFINE([HAVE_NLA_PARSE_DEPRECATED_STRICT])])
-  OVS_FIND_OP_PARAM_IFELSE([$KSRC/include/net/rtnetlink.h],
-                           [validate], [extack],
-                           [OVS_DEFINE([HAVE_RTNLOP_VALIDATE_WITH_EXTACK])])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h],
-                  [__skb_set_hash])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [sw_hash])
-  OVS_GREP_IFELSE([$KSRC/include/linux/skbuff.h], [skb_get_hash_raw])
-
-  if cmp -s datapath/linux/kcompat.h.new \
-            datapath/linux/kcompat.h >/dev/null 2>&1; then
-    rm datapath/linux/kcompat.h.new
-  else
-    mv datapath/linux/kcompat.h.new datapath/linux/kcompat.h
-  fi
-])
-
 dnl Checks for net/if_dl.h.
 dnl
 dnl (We use this as a proxy for checking whether we're building on FreeBSD