> On Feb. 25, 2016, 11:40 p.m., Jie Yu wrote: > > src/slave/containerizer/mesos/provisioner/backends/overlay.cpp, lines > > 124-129 > > <https://reviews.apache.org/r/43932/diff/1/?file=1268084#file1268084line124> > > > > To be safe, can you do the same thing to mark the mount as slave+shared > > (like we did in the bind backend). > > > > So the goal of doing that is: we want to make sure when slave fork a > > subprocess with a new mount namespace, it does not create an extra > > reference to the mount so that rmdir might fail later. > > Shuai Lin wrote: > Updated. I am interested in how to reprduce the potential problem, but > failed to reproduce with these shell commands: > > > ```sh > mkdir -p /tmp/rootfs/folder1 /tmp/layer1 > mount --bind /tmp/layer1 /tmp/rootfs/folder1 > > # create a subprocess with a new mount namespace > unshare -m sleep 1000 & > > # Try to remove the mount dir, Expected: rm would failed, Result: rm > succeeded. > umount /tmp/rootfs/folder1 > rm -rf /tmp/rootfs > ``` > > I've also read about https://issues.apache.org/jira/browse/MESOS-3483 and > https://www.kernel.org/doc/Documentation/filesystems/sharedsubtree.txt, but > still don't understand this problem, can you provide some links on this?
I think you're using a newer kernel. See this thread: https://lwn.net/Articles/570338/ You should be able to repo this problem using an older kernel (e.g., 3.10). - Jie ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/43932/#review120750 ----------------------------------------------------------- On Feb. 28, 2016, 5:22 p.m., Shuai Lin wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/43932/ > ----------------------------------------------------------- > > (Updated Feb. 28, 2016, 5:22 p.m.) > > > Review request for mesos and Jie Yu. > > > Bugs: MESOS-2971 > https://issues.apache.org/jira/browse/MESOS-2971 > > > Repository: mesos > > > Description > ------- > > Added overlayfs provisioning backend. > > > Diffs > ----- > > src/CMakeLists.txt b13fb23219ebb23bcfd6db062e1c814ca2114aa4 > src/Makefile.am 2a26261b513bb7c03437ed8e850c3b36b93d82f5 > src/slave/containerizer/mesos/provisioner/backend.cpp > 01d06ebc67e259272ee57ea5c75bf7077ede65c4 > src/slave/containerizer/mesos/provisioner/backends/overlay.hpp PRE-CREATION > src/slave/containerizer/mesos/provisioner/backends/overlay.cpp PRE-CREATION > src/slave/flags.cpp 1c6a87b670efde2deab4d6e3f24fd6eb3704a47d > src/tests/containerizer/provisioner_backend_tests.cpp > 25b28ef8fa5aae81e8dd0c9e33df4160dd912ce8 > src/tests/environment.cpp 6cd295f76496770774d090e0485ff87be378f74c > > Diff: https://reviews.apache.org/r/43932/diff/ > > > Testing > ------- > > sudo modprobe overlayfs > sudo make check -j4 > GTEST_FILTER='OverlayBackendTest.ROOT_OVERLAYFS_OverlayFSBackend' > > - OS: ubuntu 14.04 64bit vm > - Kernel: 4.2.0-27-generic > > > Thanks, > > Shuai Lin > >
