kni: fix build on Ubuntu-hybrids

In the case where a userspace reports itself as Ubuntu, but the
kernel isn't providing the expected version signature interface,
turn off Ubuntu specializations.

This situation happens often enough in development environments,
and with multi-distribution build servers (e.g. chroot, containers).

Signed-off-by: Alexander Guy <alexander@andern.org>
Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>

diff --git a/lib/librte_eal/linuxapp/kni/Makefile b/lib/librte_eal/linuxapp/kni/Makefile
index e0218e7..fb673d9 100644 (file)
--- a/lib/librte_eal/linuxapp/kni/Makefile
+++ b/lib/librte_eal/linuxapp/kni/Makefile
@@ -44,7 +44,7 @@ MODULE_CFLAGS += -I$(RTE_OUTPUT)/include -I$(SRCDIR)/ethtool/ixgbe -I$(SRCDIR)/e
 MODULE_CFLAGS += -include $(RTE_OUTPUT)/include/rte_config.h
 MODULE_CFLAGS += -Wall -Werror
 
-ifeq ($(shell lsb_release -si 2>/dev/null),Ubuntu)
+ifeq ($(shell test -f /proc/version_signature && lsb_release -si 2>/dev/null),Ubuntu)
 MODULE_CFLAGS += -DUBUNTU_RELEASE_CODE=$(shell lsb_release -sr | tr -d .)
 UBUNTU_KERNEL_CODE := $(shell cut -d' ' -f2 /proc/version_signature | \
                         cut -d'~' -f1 | cut -d- -f1,2 | tr .- $(comma))