Re: [PATCH v2] tools/virtio: option to build an out of tree module

From: Jason Wang
Date: Mon Feb 10 2020 - 22:19:48 EST



On 2020/2/7 äå3:35, Michael S. Tsirkin wrote:
Handy for testing with distro kernels.
Warn that the resulting module is completely unsupported,
and isn't intended for production use.

Usage:
make oot # builds vhost_test.ko, vhost.ko
make oot-clean # cleans out files created

Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
---

changes from v1:
lots of refactoring
disable all modules except vhost by default (more of a chance
it'll build)
oot-clean target

tools/virtio/Makefile | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/tools/virtio/Makefile b/tools/virtio/Makefile
index 8e2a908115c2..f33f32f1d208 100644
--- a/tools/virtio/Makefile
+++ b/tools/virtio/Makefile
@@ -8,7 +8,32 @@ CFLAGS += -g -O2 -Werror -Wall -I. -I../include/ -I ../../usr/include/ -Wno-poin
vpath %.c ../../drivers/virtio ../../drivers/vhost
mod:
${MAKE} -C `pwd`/../.. M=`pwd`/vhost_test V=${V}
-.PHONY: all test mod clean
+
+#oot: build vhost as an out of tree module for a distro kernel
+#no effort is taken to make it actually build or work, but tends to mostly work
+#if the distro kernel is very close to upstream
+#unsupported! this is a development tool only, don't use the
+#resulting modules in production!
+OOT_KSRC=/lib/modules/$$(uname -r)/build
+OOT_VHOST=`pwd`/../../drivers/vhost
+#Everyone depends on vhost
+#Tweak the below to enable more modules
+OOT_CONFIGS=\
+ CONFIG_VHOST=m \
+ CONFIG_VHOST_NET=n \
+ CONFIG_VHOST_SCSI=n \
+ CONFIG_VHOST_VSOCK=n
+OOT_BUILD=KCFLAGS="-I "${OOT_VHOST} ${MAKE} -C ${OOT_KSRC} V=${V}
+oot-build:
+ echo "UNSUPPORTED! Don't use the resulting modules in production!"
+ ${OOT_BUILD} M=`pwd`/vhost_test
+ ${OOT_BUILD} M=${OOT_VHOST} ${OOT_CONFIGS}
+
+oot-clean: oot-build
+oot: oot-build
+oot-clean: OOT_BUILD+=clean
+
+.PHONY: all test mod clean vhost oot oot-clean oot-build
clean:
${RM} *.o vringh_test virtio_test vhost_test/*.o vhost_test/.*.cmd \
vhost_test/Module.symvers vhost_test/modules.order *.d


Acked-by: Jason Wang <jasowang@xxxxxxxxxx>