[PATCH] linux-custom: Add lock to dependency installation

[Jan Kiszka <jan.kiszka@siemens.com>]

From: Jan Kiszka <jan.kiszka@siemens.com>

The build script of linux-custom requires the same lock protection as
build.sh of the dpkg builder class. Otherwise, we see the infamous build
failures again due to contention on the dpkg database lock.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 meta/recipes-kernel/linux/files/build-kernel.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/meta/recipes-kernel/linux/files/build-kernel.sh b/meta/recipes-kernel/linux/files/build-kernel.sh
index 94897ec..42c8ff6 100644
--- a/meta/recipes-kernel/linux/files/build-kernel.sh
+++ b/meta/recipes-kernel/linux/files/build-kernel.sh
@@ -13,8 +13,10 @@ REPACK_DIR="$1/../repack"
 REPACK_LINUX_IMAGE_DIR="${REPACK_DIR}/linux-image"
 REPACK_LINUX_HEADERS_DIR="${REPACK_DIR}/linux-headers"
 
-apt-get install -y -o Debug::pkgProblemResolver=yes --no-install-recommends \
-	${KBUILD_DEPENDS}
+# Lock-protected because apt and dpkg do not wait in case of contention
+flock /dpkg.lock \
+    apt-get install -y -o Debug::pkgProblemResolver=yes \
+        --no-install-recommends ${KBUILD_DEPENDS}
 
 cd $1
 make olddefconfig
-- 
2.13.6