[PATCH 1/2] Revert "buildchroot+bootstrap: rbind mount for /dev"

["Maxim Yu. Osipov" <mosipov@ilbers.de>]

This reverts commit e0feb7d62bf0612f9bb00f2120ae26bc96fb1b91.
as it causes bitbake's hangs when trying to unmount /dev.

The following scenario causes hangs on Debian 9 (stretch) systems:
 * source isar-init-build-env
 * sed -i -e 's/ISAR_CROSS_COMPILE ?= "0"/ISAR_CROSS_COMPILE ?= "1"/g' conf/local.conf
 * bitbake  -c cache_base_repo multiconfig:qemuarm-stretch:isar-image-base \
   multiconfig:qemuarm64-stretch:isar-image-base multiconfig:qemuamd64-stretch:isar-image-base
 * sudo rm -rf tmp
 * sed -i -e 's/#ISAR_USE_CACHED_BASE_REPO ?= "1"/ISAR_USE_CACHED_BASE_REPO ?= "1"/g' conf/local.conf
 * bitbake multiconfig:qemuarm-stretch:isar-image-base \
   multiconfig:qemuarm64-stretch:isar-image-base multiconfig:qemuamd64-stretch:isar-image-base

The last command hangs on the last task.

Signed-off-by: Maxim Yu. Osipov <mosipov@ilbers.de>
---
 meta/classes/buildchroot.bbclass                    | 3 +--
 meta/classes/image.bbclass                          | 2 +-
 meta/classes/isar-bootstrap-helper.bbclass          | 3 +--
 meta/classes/isar-image.bbclass                     | 2 +-
 meta/recipes-core/isar-bootstrap/isar-bootstrap.inc | 3 +--
 5 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/meta/classes/buildchroot.bbclass b/meta/classes/buildchroot.bbclass
index 0d4ff4e..d7368c4 100644
--- a/meta/classes/buildchroot.bbclass
+++ b/meta/classes/buildchroot.bbclass
@@ -27,8 +27,7 @@ buildchroot_do_mounts() {
         if ! grep -q ${BUILDCHROOT_DIR}/isar-apt /proc/mounts; then
             mount --bind ${REPO_ISAR_DIR}/${DISTRO} ${BUILDCHROOT_DIR}/isar-apt
             mount --bind ${DL_DIR} ${BUILDCHROOT_DIR}/downloads
-            mount --rbind /dev ${BUILDCHROOT_DIR}/dev
-            mount --make-rslave ${BUILDCHROOT_DIR}/dev
+            mount -t devtmpfs -o mode=0755,nosuid devtmpfs ${BUILDCHROOT_DIR}/dev
             mount -t proc none ${BUILDCHROOT_DIR}/proc
             mount --rbind /sys ${BUILDCHROOT_DIR}/sys
             mount --make-rslave ${BUILDCHROOT_DIR}/sys
diff --git a/meta/classes/image.bbclass b/meta/classes/image.bbclass
index d8fbfd5..f438f11 100644
--- a/meta/classes/image.bbclass
+++ b/meta/classes/image.bbclass
@@ -108,7 +108,7 @@ do_populate_sdk() {
     # Purge apt cache to make image slimmer
     sudo rm -rf ${SDKCHROOT_DIR}/rootfs/var/cache/apt/*
 
-    sudo umount -R ${SDKCHROOT_DIR}/rootfs/dev || true
+    sudo umount ${SDKCHROOT_DIR}/rootfs/dev || true
     sudo umount ${SDKCHROOT_DIR}/rootfs/proc || true
     sudo umount -R ${SDKCHROOT_DIR}/rootfs/sys || true
 
diff --git a/meta/classes/isar-bootstrap-helper.bbclass b/meta/classes/isar-bootstrap-helper.bbclass
index 641138a..0750a8f 100644
--- a/meta/classes/isar-bootstrap-helper.bbclass
+++ b/meta/classes/isar-bootstrap-helper.bbclass
@@ -103,8 +103,7 @@ setup_root_file_system() {
         sudo mount --bind ${REPO_BASE_DIR} ${ROOTFSDIR}/base-apt
     fi
 
-    sudo mount --rbind /dev ${ROOTFSDIR}/dev
-    sudo mount --make-rslave ${ROOTFSDIR}/dev
+    sudo mount -t devtmpfs -o mode=0755,nosuid devtmpfs $ROOTFSDIR/dev
     sudo mount -t proc none $ROOTFSDIR/proc
     sudo mount --rbind /sys ${ROOTFSDIR}/sys
     sudo mount --make-rslave ${ROOTFSDIR}/sys
diff --git a/meta/classes/isar-image.bbclass b/meta/classes/isar-image.bbclass
index 23b3a99..c65b13c 100644
--- a/meta/classes/isar-image.bbclass
+++ b/meta/classes/isar-image.bbclass
@@ -59,7 +59,7 @@ isar_image_cleanup() {
               -maxdepth 1 -name 'qemu-*-static' -type f -delete
     sudo umount -l ${IMAGE_ROOTFS}/isar-apt
     sudo rmdir ${IMAGE_ROOTFS}/isar-apt
-    sudo umount -R -l ${IMAGE_ROOTFS}/dev
+    sudo umount -l ${IMAGE_ROOTFS}/dev
     sudo umount -l ${IMAGE_ROOTFS}/proc
     sudo umount -R -l ${IMAGE_ROOTFS}/sys
     sudo rm -f "${IMAGE_ROOTFS}/etc/apt/apt.conf.d/55isar-fallback.conf"
diff --git a/meta/recipes-core/isar-bootstrap/isar-bootstrap.inc b/meta/recipes-core/isar-bootstrap/isar-bootstrap.inc
index da077d0..c19399c 100644
--- a/meta/recipes-core/isar-bootstrap/isar-bootstrap.inc
+++ b/meta/recipes-core/isar-bootstrap/isar-bootstrap.inc
@@ -243,8 +243,7 @@ isar_bootstrap() {
             "${ROOTFSDIR}/chroot-setup.sh" "setup" "${ROOTFSDIR}"
 
             # update APT
-            mount --rbind /dev ${ROOTFSDIR}/dev
-            mount --make-rslave ${ROOTFSDIR}/dev
+            mount -t devtmpfs -o mode=0755,nosuid devtmpfs ${ROOTFSDIR}/dev
             mount -t proc none ${ROOTFSDIR}/proc
             mount --rbind /sys ${ROOTFSDIR}/sys
             mount --make-rslave ${ROOTFSDIR}/sys
-- 
2.11.0